Glossary
Microscope Imaging Glossary
CCD
Charge Coupled Device: When an image is taken, the CCD is struck by light coming through the camera's lens. Each of the thousands or millions of tiny pixels that make up the CCD convert this light into electrons. The number of electrons, usually described as the pixel's accumulated charge, is measured, then converted to a digital value. This last step occurs outside the CCD, in a camera component called an analog-to-digital converter.
CMOS
Complementary Metal-Oxide Semiconductor: One of the two main types of image sensors used in digital cameras. Its basic function is the same as that of a CCD.
Color Calibration
This is the process of matching the color of two or more devices through software and/or hardware.
Color Co-Site Sampling
The ProgRes® C14plus cameras utilize color-co-site sampling to gather more relevant information from the specimen being observed. This extra information is used to examine the finest structures and measures the full true color information of the specimen, thus increasing spatial resolution.
DPI
Dots Per Inch: A measurement of the resolution of a digital photo or digital device, including digital cameras and printers. The higher the number, the greater the resolution.
Dynamic Range
Dynamic range in photography describes the ratio between the maximum and minimum measurable light intensities (white and black, respectively).
Grayscale
A photo made up of varying tones of black and white. Grayscale is synonymous with black and white.
Hermetically Sealed
Is a seal which, for practical purposes, is considered airtight in order to keep out harmful elements and help with the reliability of an instrument.
IEEE1394
Firewire Interface is a serial bus interface standard for high-speed communications and isochronous real-time data transfer, frequently used by personal computers, as well as in digital audio, digital video, automotive, and aeronautics applications.
Image Refresh Rate
The refresh rate is the number of times (or speed) a display's image is repainted or refreshed per second. The refresh rate is expressed in hertz so a refresh rate of 75 means the image is refreshed 75 times in a second.
Incident Illumination
Light directed down on an object.
Interpolation
Is a method of numerical mathematics. Each pixel is only able to detect one color - red, green or blue. A camera that utilizes interpolation would capture an image and record one color for each pixel. If a pixel is missing, a math formula is calculated (or interpolated) to determine that pixel's color based on the values of the neighboring pixels.
IR Bandpass Filter
A filtering device that permits only those components in the frequency domain whose frequencies lie between two critical values to pass through with little attenuation, all other components being attenuated. See also band-stop filter, low-pass filter, high-pass filter.
Jpeg
A standard for compressing image data developed by the Joint Photographic Experts Group, hence the name JPEG. Strictly speaking, JPEG is not a file format, it's a compression method that is used within a file format, such as the EXIF-JPEG format common to digital cameras. It is referred to as a lossy format, which means some quality is lost in achieving JPEG's high compression rates. Usually, if a high-quality, low-compression JPEG setting is chosen on a digital camera, the loss of quality is not detectable to the eye.
Megapixels
Equal to one million pixels.
Microphotography
A very small photograph requiring enlargement to bring out the details. Moire - An undesirable pattern that appears when a graphic image is displayed or printed with an inappropriate resolution. Moiré patterns are difficult to predict because they result from a complex combination of parameters: the size of the image, resolution of the image, resolution of the output device, halftone screen angle, etc.ines created by Noise - An unwanted grain pattern in an image often caused by slow shutter speeds and high ISO settings.
Photomicrography
Photography of objects under a microscope. Such opaque objects as metal and stone may be ground smooth, etched chemically to show their structure, and photographed by reflected light with a metallurgical microscope.
Pixelation
The appearance of recognizable square pixels in an image. Pixelation usually occurs when a bitmap image has been enlarged beyond optimal range for its given number of pixels.
Pixel
Picture Element: digital photographs are comprised of thousands or millions of them; they are the building blocks of a digital photo.
Peltier Cooling
The production or absorption of heat at the junction of two metals on the passage of a current. Heat generated by the passage of the current in one direction will be absorbed if the current is reversed. By cooling the sensor in a camera, the resulting image contains far less noise.
Print Resolution
Adequate resolution for printing. 300dpi or ppi (pixels per inch).