Optics and Electronics Flashcards

Vocabulary flashcards based on lecture notes about optics, electronics, cameras, optical recording, communication, and audio players.

Optics

The techniques of optics deal with light and allow cameras to record images, our eyes to observe objects, and eyeglasses to help us see details.

Electronics

The techniques of electronics deal with charge and permit devices to store and retrieve information, and amplify signals.

Optoelectronics

The combined field of optics and electronics, where rapid progress in both fields has brought them closer together.

Magnifying Glass

Bends light rays toward one another as they pass through it, allowing for magnification or image projection.

Real Image

A pattern of light, projected in space or on a surface, that exactly reproduces the pattern of light in the original scene.

Lens

A transparent object that uses refraction to form images by bending light passing through it.

Converging Lens

A lens that bends light rays toward one another, converging them to form an image.

Focusing

Adjusting the distance between the lens and the image sensor to produce a sharp image.

Diaphragm

A ring of metal strips with a central opening used to reduce the effective diameter of a lens.

Aperture

The effective diameter of a lens, controlled by the diaphragm.

Depth of Focus

The range of distances within which objects appear sharp in an image.

Focal Length

The distance between the lens and the real image it forms of a very distant object.

Object Distance

The distance between the lens and the object being photographed.

Image Distance

The distance between the lens and the real image it forms.

Lens Equation

Relates the focal length of a lens to the object distance and image distance.

f-number

Characterizes the brightness of the real image formed on the image sensor; calculated by dividing the lens’s focal length by its diameter.

Achromat

A lens composed of multiple elements to improve image quality by correcting for chromatic aberration and other technical problems.

Zoom Lens

A lens that can change the size of the real image it projects onto the image sensor by adjusting its effective focal length.

Virtual Image

An image located at a negative image distance, on the wrong side of the lens.

Optical Viewfinders

Optical viewfinders that combine real and virtual images to represent what the camera's image sensor will record.

Photodiodes

Diodes optimized to detect light, used in electronic image sensors.

Farsightedness

An eye condition where nearby objects cannot be seen sharply because the lens system has too long a focal length.

Nearsightedness

An eye condition where distant objects cannot be focused on because the lens system has too short a focal length

Diverging Lens

Bends light rays apart and has a negative focal length; used to correct nearsightedness.

Analog

Analog representations: , a continuously variable physical quantity (a radio wave’s amplitude or frequency) represents another continuously variable physical quantity (air’s density).

Digital

Digital representation: a continuously variable physical quantity is first represented by a series of numbers and then each of those numbers is represented by a set of physical quantities

Binary System

System for representing numbers using the powers of 2, requiring only two different symbols.

Encoded manner

Describes CDs and DVDs, which almost completely immune to all but the most severe playback problems.

Total Internal Reflection

Phenomenon that occurs when light tries to move from a glass core to a glass cladding, it’s reflected perfectly and thus can’t escape.

Erbium-Doped Fiber Amplifiers (EDFAs)

Used to amplify 1550-nm light in long-haul communication systems.

Transistors

These are key elements in nearly all modern electronic equipment.

Transistor

Allows the current in one circuit to control the current in another circuit.

N-channel Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET)

A type of transistor that is widely used in audio players, cell phones, video equipment, and computers.

Inverter

An electronic device that reverses an action.

Not-AND or NAND gate

An electronic device that its output bit is 1 unless both input bits are 1s.

Digital to Analog Converts (DAC)

This is the interface between the two representations of information: digital and analog