Photonics Dictionary

An antireflection coating (AR coating) is a thin film or coating applied to optical surfaces, such as lenses or windows, to minimize unwanted reflections and increase the transmission of light...

The second adjustable iris diaphragm in an optical system. In the common microscope condenser system, it usually is located beneath the substage condenser on a transmitted light microscope. When the...

An aplanatic surface is an optical surface that is specifically designed or shaped to minimize spherical aberration and coma. Spherical aberration is an optical aberration that occurs when light rays...

An aspheric mirror is an optical mirror surface that deviates from the shape of a perfect sphere, having a non-spherical surface profile. Unlike traditional spherical mirrors, which have a curved...

That viewpoint at which the angular subtenses of points in the picture are identical to angular subtenses of the original points in the scene, at the camera lens.

An instrument used to measure the light from a scene to be photographed and to indicate the camera lens and shutter settings required to expose the film correctly. The exposure time required in a...

1. The focal point. 2. To adjust the eyepiece or objective of a telescope so that the image is clearly seen by the observer. 3. To adjust the camera lens, plate, or film holder so that the image is...

A camera tube widely used in television broadcasting. It consists of three sections within a single vacuum envelope. 1. A photosensitive film sometimes called the photocathode. The scene to be...

A type of additive color photography using a lenticular structure impressed on a film base and a camera lens with a filter having three sectors of red, blue and green. Exposure of the film through...

A camera lens, used in macrophotography, that is designed and corrected to produce optimum definition of a nearby object when it is photographed at a magnification of approximately1:1.

Minimum object distance, often abbreviated as MOD, refers to the closest distance at which a camera lens or optical system is capable of producing a sharp and focused image. In photography, this term...

Oleophobic is a term used to describe substances or materials that repel or resist oils. The word oleophobic comes from the Greek words "oleo," meaning oil, and "phobos," meaning fear. Oleophobic...

Optical coatings are thin layers of materials applied to optical components, such as lenses, mirrors, filters, and prisms, to modify their reflective and transmissive properties. These coatings are...

The distortion that is the result of viewing a print from a point other than the center of perspective. The center of perspective is that viewpoint at which the angular subtenses of points in the...

Sapphire crystal refers to a transparent, single-crystal form of aluminum oxide (Al2O3) known as corundum. It is one of the hardest known materials, second only to diamond on the Mohs scale of...

A spheric lens, also known as a spherical lens, is a type of optical lens with at least one surface that is part of a sphere. This means that the lens surface is curved in a symmetrical manner,...

A small instrument containing a picture support and a pair of magnifying lenses so arranged that the left eye sees only the picture taken with the left lens of the stereo camera, and the right eye...

A meniscus that is often fitted before a camera lens to permit focusing on near objects.

A wide-angle lens is a type of camera lens that has a shorter focal length than a standard or normal lens, allowing it to capture a broader field of view. Wide-angle lenses are characterized by their...