Glossary

Aliasing

Distortion of the signal caused by overlap of the baseband signal and lower sideband signal when the signal is demodulated.

Aperture compensation Electronic compensation for frequency response degradations caused to sampled high-frequency signals by the limited aperture of CCD image sensors.

Black balance adjustment To balance the black levels of the R, G, and B channels of a video camera so that black has no color.

CCD

Charge-coupled device. A solid state imager used in most recent video cameras in place of a pickup tube. It converts input light levels into electrical charges, which are once stored and then output in the form of voltage variations.

Center marker

A cross that indicates the center of the image on the viewfinder screen.

Color conversion filter

An optical filter used with color video cameras to convert the color temperature of a light source.

Color temperature

The temperature in Kelvins (K) to represent the color of a light source.

Composite video signal

A composite video signal includes a video signal, burst signal, and sync signal.

Condensation Condensation refers to tiny droplets of water that can appear in a device, such as in the tape transport system. When condensation occurs on a video head drum, the tape may stick to the drum, which can damage not only the tape but also the VCR unit.

DCC

Dynamic Contrast Control. A video camera containing a DCC circuit can handle a wide dynamic range of luminance.

Drum

See “Head drum”.

Flare

Dark or colored flashes caused by signal overload through extreme light reflections of polished objects or very bright lights.

Flicker

Repeated change of brightness on the screen, which is caused by frequency difference between the camera’s scanning and the variations in the lightning.

Gen-lock

Abbreviation of “generator lock”. It refers to the synchronization of a VCR to a reference sync signal.

HAD

Hole-Accumulated Diode. A CCD sensor structure designed to suppress certain types of noise inherent CCDs. See also CCD.

Head drum

A metal cylinder to which a video head is attached. This drum is rotated at high speeds in synchronization with the sync signal during recording and playback.

Horizontal resolution

The capability of a CCD camera to preserve detail in the horizontal resolution.

Usually expressed as the number of vertical lines which can be distinguished in the reproduced image of a test chart.

i.LINK

i.LINK stands for IEEE1394-1995 stan-dards and their revisions. It is applied to the DV connector through which DV signals can be transmitted with AV protocol.

IRE scale

The scale to determine video signal amplitudes devised by the Institute of Radio Engineers (IRE), an American organization now called the Institute of Electrical and Electronic Engineers (IEEE). The IRE scale includes a total of 140 units, with 100 up and 40 down from zero.

PCM audio

PCM stands for “pulse code modulation.” PCM audio means audio signals that have been processed by pulse code modulation. Each analog audio signal is converted into pulses that are generated in rapid succession, and each pulse is recorded as a digital signal having a value of 0 or 1.

Pedestal level

A black level which is the absolute black level of a video signal.

Return video

This refers to a video signal returned from the VCR to the camera or from the CCU to one camera in a multi-camera system, allowing the camera operator to monitor the image output from the camera or shot on other cameras.

Appendix

Appendix 157