Human eye labeled diagram: Human Eye Ball Anatomy & Physiology Diagram
A closer look at the parts of the eye
When surveyed about the five senses — sight, hearing, taste, smell and touch — people consistently report that their eyesight is the mode of perception they value (and fear losing) most.
Despite this, many people don’t have a good understanding of the anatomy of the eye,
how vision works, and health problems that can affect the eye.
Read on for a basic description and explanation of the structure (anatomy) of your eyes and how they work (function) to help you see clearly and interact with your world.
How the eye works
In a number of ways, the human eye works much like a digital camera:
Light is focused primarily by the cornea — the clear front surface of the eye, which acts like a camera lens.
The iris of the eye functions like the diaphragm of a camera, controlling the amount of light reaching the back of the eye by automatically adjusting the size of the pupil (aperture).
The eye’s crystalline lens is located directly behind the pupil and further focuses light. Through a
process called accommodation, this lens helps the eye automatically focus on near and approaching objects, like an autofocus camera lens.
Light focused by the cornea and crystalline lens (and limited by the iris and pupil) then reaches the retina — the light-sensitive inner lining of the back of the eye. The retina acts like an electronic image sensor of a digital camera, converting optical images into electronic signals. The optic nerve then transmits these signals to the visual cortex — the part of the brain that controls our sense of sight.
Human Eye Anatomy (seen from above)
For more details about specific structures of the eye and how they function, visit these pages:
And for a description of common vision problems, see Refraction and Refractive Errors: How the Eye Sees.
READ NEXT: Space changes your eyes in some pretty unnatural ways
Page published in February 2019
Page updated in October 2021
Anatomy of the eye | Eye Structure Diagram
Structure of the eye
Side view of the structure of the eye
Diagram detailing the macula
The clear front of your eye is called the cornea. This transparent disc sits over the pupil and iris, protecting them and letting in light. It is highly sensitive. The cornea also forms the first part of the process of focusing what you look at into an image on the back of your eye (see below).
The coloured part of your eye is called the iris. The iris is made up of muscle fibres which help to control the size of the pupil. The pupil is not an actual structure but the circular opening in the middle of the iris. The pupil appears as the dark central part of the eye. The pupil can change size (through changes in the iris) in order to regulate the amount of light going through it. In darkness your pupils will get bigger to allow in more light.
The retina is a layer on the inside of the back of the eyeball. It contains highly specialised nerve cells. These convert the light which is focused there into electrical signals. These are then passed through the optic nerves to the parts of the brain which process vision and build up the picture that we see.
Near the centre of the retina is the macula. The macula is a small highly sensitive part of the retina. It is responsible for detailed central vision, the part you use when you look directly at something. It contains the fovea, the area of your eye which produces the sharpest images of all.
The white of your eye is called the sclera. This is a hard protective layer which covers all the eyeball except the cornea. The next layer beneath the sclera, between the retina and the sclera, is called the choroid. The choroid contains lots of blood vessels which provide oxygen and nutrients to the retina below. At the front of the eyeball the choroid connects with the ciliary body.
The ciliary body is a part of the eye which includes the ciliary muscle (which changes the shape of the pupil by changing the shape of the iris) and the ciliary epithelium, which produces aqueous humour. This is the liquid that fills the front of the eye. Aqueous humour is made continuously. It circulates through the front part of the eye and then drains away through an area called the trabecular meshwork, near the base of the iris.
In order for an object to be seen, the light coming from the object must hit the retina. Structures in the eye bend the light rays entering the eye so that when they reach the retina they are focused. The cornea and lens both help to do this. The cornea gives the initial bend to the light but the lens is the fine tuner. The lens can change shape with the help of the ciliary body which contains fine muscle fibres that pull on it. Depending on the angle of the light coming into it, the lens becomes more or less curved (convex). This alters its strength and allows it to focus the light correctly on to the back of the eye. This is very similar to the action of a lens in a camera which focuses the light on to the film.
The globe of the eye needs to keep its shape so that light rays are focused accurately on to the retina. Most of the eye is therefore filled with a jelly-like substance called the vitreous humour.
The movement of each eye is controlled by six muscles that pull the globe of the eye in various directions. They work together in a synchronised way. For example, to look left, the lateral rectus muscle of the left eye pulls the left eye outward and the medial rectus of the right eye pulls the right eye towards the nose. At the same time levator palpebrae superioris lifts the upper eyelid.
The upper and lower eyelids help to protect the eye, and keep its surface moist. The upper eyelid is more mobile and is attached to a special muscle, called the levator palpebrae superioris. This muscle allows you to control the upper eyelid. Eyelids help to spread the tear film across the eye by blinking. They also produce a special oil which slows down the evaporation of the tear film.
The eyelids are made up of several different layers, including the conjunctiva. The conjunctiva is a clear layer which lines the inside of your eyelid and covers the white of the eyeball. When the blood vessels in this conjunctiva become enlarged they can be seen, giving a bloodshot appearance.
Eyelashes help to stop debris and direct sunlight from entering the eyes.
The sensitive surface of the eye needs to be kept moist. The eyes are in constant contact with your eyelids. Without lubrication, the friction between the two layers of conjunctiva would cause rubbing. To prevent this, and to help remove debris, the eye produces a tear film. The tear film is made up from three layers – the main middle watery layer, the thin outer oily (lipid) layer and the thin inner layer of mucus.
Eye with eyelid detail
Eye and tear production
The main middle watery layer is what we think of as tears. The watery fluid comes from the lacrimal glands. There is a lacrimal gland just above, and to the outer side, of each eye. The lacrimal glands constantly make a small amount of watery fluid which drains on to the upper part of the eyes. When you blink, the eyelid spreads the tears over the front of the eye.
Tiny glands in the eyelids (meibomian glands) make a small amount of lipid liquid which covers the outer layer of the tear film. This layer helps to keep the tear surface smooth and to reduce evaporation of the watery tears.
Cells of the conjunctiva at the front of the eye and inner part of the eyelids also make a small amount of mucus-like fluid. This helps the watery tears to spread evenly over the surface of the eye.
Tears then drain down small channels (canaliculi) on the inner side of the eye into a tear sac. From here they flow down a channel called the tear duct (also called the nasolacrimal duct) into the nose. You can see the opening of the nasolacrimal duct as a tiny hole in the inner corner of your lower eyelid.
Tear formation in people occurs more if the eyes are irritated. It can also occur in response to emotion. When this happens the lacrimal glands produce more lacrimal fluid which spills over the eyelids.
How does the visual system work?
The eyes receive light from many different directions and distances. To be seen, all this light must focus on the comparatively tiny area of the retina. This means the eyes have to bend light from different angles and directions.
Firstly, light passes through the transparent cornea. Most bending of light occurs here. Light then travels through the pupil and hits the lens. The lens also bends light, increasing the amount focused on the highly specialised cells of the retina.
In short-sightedness (myopia), the eye mistakenly focuses the rays of light on a point before the retina. The focusing system is tending to be too powerful for the length of the eye. This particularly affects vision of distant objects, which need the least powerful focusing activity from the eye.
In long-sightedness (hypermetropia) the opposite is true and light converges on a point behind the retina. This particularly affects vision of near objects, which need the strongest focusing activity, and means nearby objects can’t be seen well.
The retina is made up of millions of light-sensitive nerve cells called photoreceptors. Photoreceptors contain special chemicals which change when light hits them. This change causes an electrical signal which is sent to the brain via the optic nerve. Different types of photoreceptor allow us to see in a huge range of different conditions, from dark to light, and all the colours of the rainbow.
There are two kinds of photoreceptors: rods are very sensitive and help us to see in dim light. They are also very sensitive to movements, particularly at the edge of our vision – but they are not sensitive to colour. For this reason colour perception is partly lost when there is little light. Cones give us colour vision; they function best in bright light. Cones are most concentrated in our area of central vision.
The electrical signals from the photoreceptors travel to a part of the brain called the thalamus via the optic nerve. This area acts as a relay station, combining information from the two eyes and sending on the information received to an area of brain called the visual cortex. The visual cortex is a specialised part of the brain which processes visual information. Located at the back of the head, it interprets the electrical signals to obtain information about the object’s colour, shape and depth. Other parts of the brain then put this information together to create the whole picture.
Some disorders of the eyes and vision
Vision and Eye Diagram: How We See
Light reflects off the object we’re looking at and enters the eye through the cornea, a clear, thin, dome-shaped tissue at the very front of the eye. The cornea has a curvature to it and covers the eye, kind of like a crystal covering the face of a watch. “When rays of light enter the eye, they’re sort of parallel to each other,” says Rosen. “But as they pass through the cornea, they bend and start to converge, almost coming to a point on the retina.” From there, light travels through a clear fluid, called the aqueous humor, which fills small chambers behind the cornea, nourishes the eye and helps retain pressure to help the eye retain its shape.
As the light continues, it passes through an opening called the pupil , that black dot at the center of the eye. The pupil is surrounded by the iris, the colored part of the eye. It’s the iris’s job to control how much light the pupil lets into the eye. When there is bright light, the iris uses muscles to change the size of the pupil (making it contract) to let in less light. When there is low light, the iris opens up the pupil, making it wider, to let in more light.
Next, the light penetrates the lens, a transparent structure that works with the cornea to bend light and focus it onto the retina, which is located in the back of the eye. “The lens accumulates proteins as we age, causing a cloudy lens, or cataracts,” says Jaclyn Haugsdal, M.D., clinical assistant professor of ophthalmology and visual sciences at the University of Iowa Carver College of Medicine. Small elastic muscles, known as ciliary muscles, which are attached to the lens, help it change its shape in order to focus at various distances. When these muscles contract, the curvature of the lens increases, allowing us to see objects that are close up. When these muscles relax, the lens becomes flattened, helping with long-range vision.
The large space behind the lens, in the back portion of the eye, is filled with a clear, gel-like substance, called the vitreous. The gel helps keep the space in the middle of the eye clear so light can reach the retina. “It also provides some elasticity to the eye, helping it keep its shape,” says Rosen. “For example, rubbing your eyes causes your eye pressure to spike, but it returns to normal when you stop rubbing. Or, if you poke your eye, it doesn’t automatically deflate because this kind of elastic material fills the eye and absorbs the impact, preventing it from causing much damage.”
Diagram of Eye – Labelled Diagram of Human Eye, Explanation and Function
The human eye is one of the most important organs of the human body which when interacts with light gives us the sense of sight or vision. There are two kinds of cells in the eye namely rods and cones. The basic function of Rods and Cones are conscious light perception color differentiation and perception of depth. The human eye is capable of distinguishing between about 10 million colors, and it can also detect a single photo. The human eye is a part of the sensory nervous system.
Labelled Diagram of Human Eye
The eyes of all mammals consists of a non-image-forming photosensitive ganglion within the retina which receives light, adjusts the dimensions of the pupil, regulates the availability of melatonin hormones, and also entertains the body clock.
The anterior chamber of the eyes is the space between the cornea and therefore the iris and is crammed with a lubricating fluid, aqueous humor .
The vascular layer of the attention , referred to as the choroid contains the animal tissue .
The iris and therefore the choroid are connected by the membrane .
Fovea is a minute pit placed in the macula of the retina that helps in forming a clear vision.
Cornea is a dome-shaped tissue covering the front of the eye.
Iris is that the coloured a part of the eyes and controls the quantity of light entering the eyes by regulating the dimensions of the pupil.
The lens is located just behind the iris. Its function is to focus the light on the retina.
The optic nerve helps in transmitting the electrical signals from the retina to the brain.
Pupil is the opening at the centre of the iris. Its size changes with the amount of light.
The retina lines contain several photoreceptors.
Vitreous humour is the fluid present within the centre of the attention and provides form and shape to the eyes.
Operation of an Human Eye
The operation of a human eye can be compared to that of a digital camera because of the following reasons –
Light focuses mainly on the cornea, which acts sort of like an optical lens .
The iris controls the light that reaches by adjusting the dimensions of the pupil, and thus it functions just like the diaphragm of a camera.
The lens of the attention is found behind the pupil, and it focuses light. This lens helps the attention to automatically specialise in near and distant objects, and also the approaching objects, like an autofocus optical lens .
The cornea and lens focus light to succeed in the retina, which may be a light-sensitive zone present on the inner lining of the rear of the attention .
The retina converts optical phenomenon images into electronic signals, and thus it acts as a bitmap sensor of a camera . These electric signals are then transmitted by the nervus opticus to the visual area , which is liable for the sense of sight.
Function of the Human Eye
Human eyes are a specialized sense organ capable of receiving visual images and producing the sense of sight in us. The eye receives direct oxygen through the aqueous humour. The aqueous humour nourishes the cornea, lens, and therefore the iris, by carrying nutrients, removing wastes materials excreted by the lens, and maintaining the form and structure of the eyes. The aqueous humour is liable for providing shape to the eyes. It must be clear to function properly.
Function of Lens in the Human Eye
The lens may be a transparent flexible tissue located directly behind the iris and therefore the pupil. To focus light and images on the retina becomes the basic function of the lens. The cornea and the lens are responsible for focusing the image in the retina.
Due to the elastic & flexibility the lens has, it can change its curved shape to focus on nearby or distant objects as per the requirements. The lens provides around 25-35 you look after the entire focusing power of the eyes.
The lens is attached to the ciliary muscles, which contracts and releases in order to change the shape of the lens and also its curvature.
Human Eye | Vision Direct UK
Anatomy of the eye
Click on the buttons to learn about the functionality of the optic nerve, pupil, conjunctiva and other parts of the eye.
The clear, dome-shaped front part of the eye that helps your eye focus light, so you can see clearly.
The opening in the centre of the iris that controls the amount of light passing through to the back of the eye.
The transparent, elastic structure inside the eye that bends to focus light rays onto the retina.
The clear, watery fluid in the front of the eyeball made up of water, sugars and various nutrients. It nourishes the cornea and the lens and gives the eye its shape.
The coloured part of the eye surrounding the pupil that controls the amount of light that enters into the eye.
A clear, thin transparent layer of tissue that covers part of the front surface of the eye and the inner surface of the eyelids.
The dense protective tissue of the eyeball that forms the ‘white’ of your eye. Sclera forms over 80% of the surface area of the eyeball, from the cornea to the optic nerve.
A clear gel-like substance that occupies the space between the crystalline lens and the retina and transmits initial light waves.
Optic Disc (Blind Spot)
A disc on the retina that is the point of entry of the optic nerve. It lacks visual receptors, so it’s also known as the blind spot.
The central part of the retina that allows us to see fine details.
The central part of the macula, necessary for activities where visual detail is important, such as driving or reading.
The light-sensitive nerve layer that lines the inside of the back of the eye. It creates electrical signals that travel through the optic nerve to the brain.
A bundle of nerve fibres that connect the retina with the brain and help us interpret what we see.
|Eye Parts||Description and Functions|
|Cornea||The cornea is the outer covering of the eye. This dome-shaped layer protects your eye from elements that could cause damage to the inner parts of the eye. There are several layers of the cornea, creating a tough layer that provides additional protection. These layers regenerate very quickly, helping the eye to eliminate damage more easily. The cornea also allows the eye to properly focus on light more effectively. Those who are having trouble focusing their eyes properly can have their corneas surgically reshaped to eliminate this problem.|
|Sclera||The sclera is commonly referred to as the “whites” of the eye. This is a smooth, white layer on the outside, but the inside is brown and contains grooves that help the tendons of the eye attach properly. The sclera provides structure and safety for the inner workings of the eye, but is also flexible so that the eye can move to seek out objects as necessary.|
|Pupil||The pupil appears as a black dot in the middle of the eye. This black area is actually a hole that takes in light so the eye can focus on the objects in front of it.|
|Iris||The iris is the area of the eye that contains the pigment which gives the eye its color. This area surrounds the pupil, and uses the dilator pupillae muscles to widen or close the pupil. This allows the eye to take in more or less light depending on how bright it is around you. If it is too bright, the iris will shrink the pupil so that they eye can focus more effectively.|
|Conjunctiva Glands||These are layers of mucus which help keep the outside of the eye moist. If the eye dries out it can become itchy and painful. It can also become more susceptible to damage or infection. If the conjunctiva glands become infected the patient will develop “pink eye.”|
|Lacrimal Glands||These glands are located on the outer corner of each eye. They produce tears which help moisten the eye when it becomes dry, and flush out particles which irritate the eye. As tears flush out potentially dangerous irritants, it becomes easier to focus properly.|
|Lens||The lens sits directly behind the pupil. This is a clear layer that focuses the light the pupil takes in. It is held in place by the ciliary muscles, which allow the lens to change shape depending on the amount of light that hits it so it can be properly focused.|
|Retina||The light focused by the lens will be transmitted onto the retina. This is made of rods and cones arranged in layers, which will transmit light into chemicals and electrical pulses. The retina is located in the back of the eye, and is connected to the optic nerves that will transmit the images the eye sees to the brain so they can be interpreted. The back of the retina, known as the macula, will help interpret the details of the object the eye is working to interpret. The center of the macula, known as the fova will increase the detail of these images to a perceivable point.|
|Ciliary Body||Ciliary body is a ring-shaped tissue which holds and controls the movement of the eye lens, and thus, it helps to control the shape of the lens.|
|Choroid||The choroid lies between the retina and the sclera, which provides blood supply to the eye. Just like any other portion of the body, the blood supply gives nutrition to the various parts of the eye.|
|Vitreous Humor||The vitreous humor is the gel located in the back of the eye which helps it hold its shape. This gel takes in nutrients from the ciliary body, aqueous humor and the retinal vessels so the eye can remain healthy. When debris finds its way into the vitreous humor, it causes the eye to perceive “floaters,” or spots that move across the vision area that cannot be attributed to objects in the environment.|
|Aqueous Humor||The aqueous humor is a watery substance that fills the eye. It is split into two chambers. The anterior chamber is located in front of the iris, and the posterior chamber is directly behind it. These layers allow the eye to maintain its shape. This liquid is drained through the Schlemm canal so that any buildup in the eye can be removed. If the patient’s aqueous humor is not draining properly, they can develop glaucoma.|
Anatomy of the eye – Moorfields Eye Hospital
Our eyes might be small, but they provide us with what many people consider to be the most important of our senses – vision.
How vision works
Vision occurs when light enters the eye through the pupil. With help from other important structures in the eye, like the iris and cornea, the appropriate amount of light is directed towards the lens.
Just like a lens in a camera sends a message to produce a film, the lens in the eye ‘refracts’ (bends) incoming light onto the retina. The retina is made up by millions of specialised cells known as rods and cones, which work together to transform the image into electrical energy, which is sent to the optic disk on the retina and transferred via electrical impulses along the optic nerve to be processed by the brain.
Anatomy of the eye
What makes up an eye
- Iris: regulates the amount of light that enters your eye. It forms the coloured, visible part of your eye in front of the lens. Light enters through a central opening called the pupil.
- Pupil: the circular opening in the centre of the iris through which light passes into the lens of the eye. The iris controls widening and narrowing (dilation and constriction) of the pupil.
- Cornea: the transparent circular part of the front of the eyeball. It refracts the light entering the eye onto the lens, which then focuses it onto the retina. The cornea contains no blood vessels and is extremely sensitive to pain.
- Lens: a transparent structure situated behind your pupil. It is enclosed in a thin transparent capsule and helps to refract incoming light and focus it onto the retina. A cataract is when the lens becomes cloudy, and a cataract operation involves the replacement of the cloudy lens with an artificial plastic lens.
- Choroid: the middle layer of the eye between the retina and the sclera. It also contains a pigment that absorbs excess light so preventing blurring of vision.
- Ciliary body: the part of the eye that connects the choroid to the iris.
- Retina: a light sensitive layer that lines the interior of the eye. It is composed of light sensitive cells known as rods and cones. The human eye contains about 125 million rods, which are necessary for seeing in dim light. Cones, on the other hand, function best in bright light. There are between 6 and 7 million cones in the eye and they are essential for receiving a sharp accurate image and for distinguishing colours. The retina works much in the same way as film in a camera.
- Macula: a yellow spot on the retina at the back of the eye which surrounds the fovea.
- Fovea: forms a small indentation at the centre of the macula and is the area with the greatest concentration of cone cells. When the eye is directed at an object, the part of the image that is focused on the fovea is the image most accurately registered by the brain.
- Optic disc: the visible (when the eye is examined) portion of the optic nerve, also found on the retina. The optic disc identifies the start of the optic nerve where messages from cone and rod cells leave the eye via nerve fibres to the optic centre of the brain. This area is also known as the ‘blind spot’.
- Optic nerve: leaves the eye at the optic disc and transfers all the visual information to the brain.
- Sclera: the white part of the eye, a tough covering with which the cornea forms the external protective coat of the eye.
- Rod cells are one of the two types of light-sensitive cells in the retina of the eye. There are about 125 million rods, which are necessary for seeing in dim light.
- Cone cells are the second type of light sensitive cells in the retina of the eye. The human retina contains between six and seven million cones; they function best in bright light and are essential for acute vision (receiving a sharp accurate image). It is thought that there are three types of cones, each sensitive to the wavelength of a different primary colour – red, green or blue. Other colours are seen as combinations of these primary colours.
Last updated: 16th November 2017
Link a chart title, label, or text box to a cell on
To easily update a chart or axis title, label, or text box added to a chart, you can link it to a cell on the chart. Changes made to the data in this cell will automatically appear in the chart.
Note: Linking options are currently not available for the following chart types: • Maps • Treemap • Sun Rays
Bar Graph •
• Box &
Whiskers • Cascading
In the chart, click the title, text box, or text box that you want to link to a cell on the sheet, or select it from the list of chart elements, do the following:
Click the chart.
Displays of the Chart Tools tab.
Note: The names of the tabs in the chart tool differ depending on the version of Excel chart you are using.
On the Format tab, in the Current Selection group, click the arrow next to Chart Area , and then select the desired chart element.
In the formula bar, enter an equal sign ( = ).
Select a cell on it with data that should be displayed in the title, caption or text field of the chart.
Tip: You can also enter a cell reference on it.Specify sheet name and exclamation point, for example Sheet1! F2
You can always ask the Excel Tech Community a question or ask for help in the Answers community.
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90,000 10 errors in using graphs and charts
“There are three types of lies: lies, blatant lies and statistics” – Benjamin Disraeli.
To paraphrase this famous phrase, graphs and charts can lie too. Not only are the visualizations based on numbers (the origin of which is often questionable), but they can also play a cruel joke with our perception, intentionally or unintentionally distorting information, confusing the audience, or at best making this information obscure.
Now there is so much data that it is already unrealistic to perceive them using tables.At the same time, charts allow us to quickly and efficiently analyze large datasets, highlight relationships and patterns, focus on the important, and in the end – it’s just beautiful!
Of course, not all economists and financiers are experts in data visualization, as a result of which we are constantly faced with incomprehensible graphs and charts. This article describes 10 of the most common errors in using visualizations and helpful tips for resolving them:
1.The vertical Y-axis does not start at 0
Bar charts (bar charts) are primarily used to visualize relative sizes. Accordingly, if the user of information sees that one bar on the graph is twice as large as the other, he subconsciously concludes that there is a twofold difference in the quantitative value. But this comparison will be wrong if the axis does not start from zero.
It is easier to demonstrate this effect with an example. The chart on the left shows the company’s product margins.It is immediately striking that bananas bring in 3 times more profit than oranges. But if you look at the graph on the right, which displays exactly the same information, the difference is not so dramatic.
This error, which leads to a significant distortion of the proportions, is the most common. And all because Excel, by default, helpfully selects the most beautiful visualization method, automatically determining the range of axis values. Therefore, you have to always be on the lookout to prevent games with our perception and reflect the data as adequately as possible.
It should be noted that this rule has one limitation – minor changes are poorly distinguished on histograms. If it is necessary to change the starting point of the axis to show small fluctuations, it is preferable to use a line graph, as in the example below.
2. The time axis incorrectly reflects the integrity of the period
Let’s imagine a situation when in the first half of the year the company had sales only in January, February, April and June.And for March and May there were no sales. In the diagram on the left, we simply do not see these “dips”.
This is because Excel interprets months in this case as a category, not as a continuous dimension, and makes equal tick marks for unequal intervals. In other words, for Excel, the January, February, April, June series is similar to the apple, orange, banana, peach series. In this case, the data source must explicitly state that sales were zero in March and May.
3. Selecting the wrong type of schedule
The graph allows you to express the idea that the data carries in the most complete and accurate way, so it is very important to choose the appropriate type of graph. Bar charts (bar charts) are better understood when comparing categories, line charts when showing a category change over time, and pie charts to visualize structure. It is better not to use scatter charts for conversations with non-technical specialists, they are more suitable for analyzing raw raw data.
The first example shows the difference in perception of a line and a bar chart when comparing categories (data source is the same):
And this example immediately shows which of the types of graphs more clearly and efficiently conveys the time dynamics of indicators:
4. Using 3D Effects
Beauty in graphics is not always synonymous with clarity. Due to the addition of an additional third dimension to the diagrams, a strong distortion of the proportions occurs according to the principle of a close / distant object.The effect of this can be seen in the example below. Which chart do you think is easier to read?
For this reason, most 3D visualizations at least do not make the information clearer. In the 3D pie chart below, which sector is larger: green or blue, red or purple? Visually, the company sold much more pears than apples. In fact, the green and blue sectors are absolutely equal, just as red and lilac are equal. This can be clearly seen in the 2D version of this diagram on the right.
So if you don’t have a really, really good reason to use 3D charts, it’s best to just forget about them.
5. Bad or redundant design
Of course, the taste and color of all markers are different – but nevertheless, minimalism is considered good form in visualizations, the desire to remove everything unnecessary, everything that can distract from the essence of information. Below is an example of a not very successful visualization style (break-even point of some kind of production).
The following points can be highlighted, which definitely do not contribute to a better perception:
- no header;
- missing axes signatures;
- an abundance of black auxiliary lines;
- vertical or diagonal inscriptions – they are much worse readable;
- separate legend (of course with a black border line), if it is possible to label the data on the diagram itself.
Now let’s look at the same information, only in a slightly different form.Comments here, I think, are superfluous.
6. Too many categories
Splitting a pie chart (or even a regular histogram) into a large number of sectors makes it impossible to quickly compare categories, especially small ones. Often it turns out just informational rubbish.
Best visualization practices recommend dividing the structure into a maximum of 4-5 parts. As a last resort, you can always apply category grouping or divide the information into several diagrams.The clarity of this error is demonstrated in the example below.
7. Lack of accent
Any visualization is a way of presenting information, a way to convey to the audience some thought, idea. You’re going to say something with your schedule – do it! If there is no accent on the diagram, the gaze does not cling to anything – you risk getting the unfocused attention of the information consumer. Below is an example of graphs with a clear emphasis.
This is especially important when preparing visualizations for presentations.It is often necessary to select elements on the graphs almost manually in order to purposefully control attention, to show where to look. Highlighting in contrast is the best way. You can also make annotations – text inserts explaining the behavior / change of the graph at the specified points.
One more tip – slide presentations should show as little information as needed to reinforce the central line of the story. Detailed transcripts can always be done in the handout (which, in turn, is best distributed at the very end, otherwise people will simply be distracted).
8. Distortion when grouping into the category “Others”
The “Others” category is best done only when only a small part of the data is grouped into it. Otherwise, you can easily distort the perception of information. For example, look at these two graphs:
In the first graph, the “Others” category is hidden, which could lead to the idea that these top 10 films have collected the bulk of the cumulative box office. The second graph shows a slightly different picture.
9. Incorrect use of averaged data
For a visual demonstration of this error, look at the small visualization on the left. What can you say about it? We see positive sales dynamics, the company is doing well. But if you expand the same information on the categories of goods sold, then the situation appears in a completely different light. It turns out that all categories, except for tangerines, are experiencing a decline in sales. And only due to the tangerines, the company as a whole was able to sell in 2016.more than in 2015. From this point of view, there is clearly something to think about.
The first graph shows absolutely correct information. But on it we see only part of the truth, while the second graph demonstrates the whole truth, deciphering the averaged numbers. Averages or totals can be a great way to quickly assess a business for some key metrics, but you need to take them right and always remember that they can hide a lot of interesting information.
10. Pie charts do not display integer (100%)
Pie charts are sometimes mistakenly used not only to demonstrate the structure of a whole, but simply to compare categories – for example, average salaries by department (left visualization). The result is information about nothing. After all, the sum of average salaries by department is not equal to the average salary at the enterprise. Instead, it is more correct to use aggregation by the number of employees, or the amount of the total payroll (as in the diagram on the right).
Graphs and charts help you make sense of data and turn information into knowledge. It is very important to use this powerful tool correctly. After all, an incorrectly implemented visualization can not only slow down the perception of data, but also distort it, pushing for the wrong decisions. Understanding common graphic mistakes will help you avoid them and realize the full potential of visualizations, make clear, balanced, honest graphs and diagrams.
Author: Victor Ryzhov
90,000 Change the look of text and chart labels in Pages on Mac
Charts have labels that display the values of specific data points. You can select their format (for example, numbers, currency values, or percentages), change where they appear, and so on.
Click the chart.
In the Format sidebar, click the Series tab.
Do one of the following.
Bubble chart. Click the disclosure arrow next to Bubble Labels, select the Values check box, then click the Value Data Format pop-up menu and choose a value format.
Scatter diagram. Click the disclosure arrow next to Value Labels, select the Values check box, and then click the pop-up menu and choose a number format.
Other chart types. Click the disclosure arrow next to Value Labels, then click the pop-up menu and choose a number format.
To hide value labels, clear the Values check box or choose None from the pop-up menu.
Fine-tuning value labels (these controls are not available for all chart types).
Sets the number of decimal places. Press the up or down arrow.
Display of the group separator. Select the Thousand Separator check box.
Add suffix or prefix. Enter text. It will be added to the beginning or end of the label.
Select a place for labels. Click the Placement pop-up menu and choose an option (for example, Top, Center, Inside, and so on; the options available depend on the type of chart).
To change the font, color, and style of labels, click any label in the chart and use the controls in the Font section of the sidebar.
Only the labels for the selected data series are changed. To change labels for another series, click one of its labels and make your changes.
To select multiple series, click a value label, then Command-click a value label in another series. To select all series, select the value label, then press Command-A.
When a chart is created, AutoFit is automatically applied to value labels to avoid overlap.To see all the value labels, clear the AutoFit check box.