What Is a Fundus Camera? How It Works & Uses

What is a fundus camera? What can it capture?

Fundus cameras are used to photograph the back of the eye. The image shows the retina and usually includes the optic disc, macula, and the blood vessels that run across it.

The photo becomes part of the patient’s record. If another photo is taken at a later visit, the doctor can pull up the older one and compare the two. Changes are often easier to judge when there is an earlier image to look at, rather than just a few lines of notes from the last exam.

Annotated retinal fundus image showing the optic disc, macula, retinal blood vessels, and retina.

How much you can see depends on the camera. A regular fundus camera mostly shows the center of the retina. Wide-angle and ultra-wide-angle cameras can capture more of the retina, including areas farther out toward the edges.

So the photo isn’t just for that one visit. It can stay in the patient’s record and be checked again later. That gives the doctor something real to compare, instead of having to rely on notes alone.

How Does a Fundus Camera Work?

A fundus camera uses light to take a picture of the retina. The light goes in through the pupil, reaches the back of the eye, and the camera records the image that comes back.

Since everything has to pass through the pupil, getting a clean image is not always easy. The cornea can reflect some of the light and leave glare in the photo. Fundus cameras are designed to reduce this as much as possible so the retina stays clear in the image.

The basic idea hasn’t changed much over the years. Newer fundus cameras just use digital sensors, lenses, filters, and different light sources to get a clearer image.

Diagram showing how a fundus camera sends light through the pupil to the retina and captures reflected light with a camera sensor.

Aligning the Eye

Before taking the photo, the camera needs to line up with the patient’s pupil. With a tabletop fundus camera, the patient usually sits in front of the machine with their chin and forehead resting on the supports and looks at a small target. With a handheld camera, the operator moves the camera toward the eye and adjusts the position by hand.

If the camera is not lined up well, the photo may have dark areas, glare, or parts of the retina may be missing.

Illuminating and Focusing on the Retina

After the camera is lined up, light passes through the pupil to the retina. Some non-mydriatic cameras use infrared light or dim light while the operator is getting the eye into position, so the eye can be lined up and focused before the brighter flash is used.

The camera then focuses on the retina. Depending on the model, this may be done by hand, with autofocus, or mostly automatically.

Capturing the Fundus Photograph

Once the image looks clear, the photo is taken. The shot itself is very quick, although the patient may notice a short flash. The image usually appears on the screen right away, so the operator can check it before the exam is finished.

The first photo is not always good enough. It may be blurry, too dark, or have glare. Eyelashes, eyelids, patient movement, small pupils, or cloudy areas inside the eye can also affect the picture. If that happens, the operator can adjust the position or focus and take another photo.

Comparison of a clear gradable fundus image and a poor-quality fundus image affected by blur, reflection, and obstruction.

The photo has to show the area the doctor wants to look at. If part of the retina is cut off, out of focus, or covered by glare, they may simply take another picture.

The camera sends light through the pupil and photographs the retina. A lot of it comes down to getting the eye and the camera in the right position. When that is right, the picture is usually much easier to see.

What Is a Fundus Camera Used For?

Fundus photos are often kept in the patient’s chart so there is an actual picture to look back at later. Depending on the visit, the doctor may be looking mainly at the optic disc, the macula, or another part of the retina.

They are used a lot in diabetic eye care. A small bleed or another change in the retina may show up in the photo. Doctors also use these images when they are watching the optic nerve in glaucoma, the macula in AMD, or changes in the retinal blood vessels.

At a later visit, the old image can be opened next to the new one. If something looks different, it is easier to see in the pictures. The image can also be shown to the patient or sent to another doctor if needed.

Sometimes the photo is taken in one clinic and reviewed somewhere else. This happens in some screening programs. And if the photo shows something that needs a closer look, the doctor may use OCT, dilate the eye, check eye pressure, or do another test.

What Are the Main Types of Fundus Cameras?

You’ll often see the same fundus camera described with several terms at once. A handheld camera, for example, may also be non-mydriatic and fully automated. That’s because these terms describe different things — the camera’s form, whether dilation is needed, how much of the retina it can capture, and how much of the imaging process it handles automatically.

Classification	Common Types	Main Difference
Pupil requirement	Mydriatic / Non-mydriatic	Whether pharmacological pupil dilation is routinely required
Physical format	Tabletop / Handheld or portable	How the patient and camera are positioned
Field of view	Standard / Widefield / Ultra-widefield	How much of the retina is captured
Operation	Manual / Assisted / Automated	How much of the imaging process is controlled by the operator

Mydriatic vs Non-Mydriatic Fundus Cameras

Some cameras work better after the pupil has been dilated. The bigger opening can make it easier to get a clear view, especially with small pupils or when the doctor wants to see more of the retina.

Other cameras can take the picture without using drops first. That is quicker and works well for many routine checks. But sometimes the view still is not good enough, so dilation may be used after all.

Tabletop vs Handheld Fundus Cameras

A tabletop fundus camera stays in one spot. The patient sits in front of it, rests their chin and forehead on the supports, and the picture is taken from there.

A handheld camera goes to the patient instead. It can be moved between rooms and may be easier to use with patients who cannot sit comfortably at a tabletop machine.

Both do the same basic job. The main difference is how the camera is used during the exam.

Standard, Widefield, and Ultra-Widefield Imaging

Field of view is simply how much of the retina fits into one picture.

A standard fundus camera mainly shows the central part of the retina, including the optic disc and macula. Widefield and ultra-widefield cameras show more of the retina, especially areas farther out toward the edges. That can be useful when the doctor wants to check the peripheral retina, but for many routine exams, a standard image may be enough.

Manual and Automated Fundus Cameras

Some fundus cameras need more work from the operator. They may have to line up the eye, adjust the focus, set the exposure, and decide when to take the picture.

Other cameras do more of that on their own. They may have autofocus, auto exposure, alignment help, or automatic capture. This can make the process quicker and easier, but the eye still needs to be in the right position and the final picture still needs to be clear.

Fundus Photography vs OCT and Ophthalmoscopy

A fundus photo shows what the back of the eye looks like in color. The optic disc, macula and blood vessels can all be seen in the picture.

OCT is different. It looks through the retina and shows the layers inside it. If a doctor sees something on the fundus photo that needs a closer look, an OCT may be done to see what is going on underneath.

Method	What It Primarily Provides	Common Role
Fundus photography	Two-dimensional retinal photograph	Documentation, screening, comparison over time
OCT	Cross-sectional retinal structure	Detailed assessment of retinal layers
Ophthalmoscopy	Real-time view of the fundus	Direct clinical examination

Comparison of fundus photography, OCT, and ophthalmoscopy showing a 2D retinal image, cross-sectional retinal structure, and direct eye examination.

With ophthalmoscopy, the doctor looks directly into the eye and sees the fundus in real time. Nothing is automatically saved. A fundus camera adds a photograph that can be kept in the record and checked again later.

OCT does something different again: it shows the retina layer by layer. Depending on what the doctor needs to look at, more than one of these may be used during the same visit.

Frequently Asked Questions

What is fundus photography?

It’s simply a photo of the back of the eye. The retina, optic disc, macula, and blood vessels are usually visible in the image.

What is a fundus camera used for?

Mostly to take a closer look at the retina and keep a record of what was seen. Those photos can also be useful later if the doctor wants to compare changes from one visit to another.

Is fundus photography the same as retinal imaging?

Not quite. Fundus photography is one way to image the retina. OCT is another. They don’t show the eye in exactly the same way.

Does a fundus camera require pupil dilation?

Not every time. Some cameras can get a good photo without drops. If the pupil is small or the view is not clear enough, dilation may still be needed.

Can a fundus camera see the entire retina?

Usually no. A standard camera only captures part of the retina in one photo. Widefield systems can show more, especially farther out toward the edges.

Fundus Photography in Modern Eye Care

A fundus photo gives the doctor something to look back at. If the patient returns later, the new image can be compared with the old one to see whether anything has changed.

Different cameras suit different setups. Some stay in one exam room, some can be carried between rooms, and some show more of the retinal periphery. If the photo does not tell the whole story, OCT, dilation, or another eye exam may be the next step.