Appendix A: Glossary
Menu ' A list of selectable options displayed on the screen.
NTSC Video | ' A video output format of some video tape and disk players. There are two types of |
| NTSC (National Television Standards Committee) video: NTSC 3.58 and NTSC |
| 4.43. NTSC 3.58 is used primarily in North America and Japan. NTSC 4.43 is less |
| commonly used. |
Optical Screen | ' A type of |
| image brightness in front of the screen. Screen gain is usually greater than 1 but |
| audience viewing angles are reduced. |
PAL Video | ' PAL (Phase Alternating Line) video is a 50 Hz standard with 768 x 576 resolution. It |
| is found on some video tape and disk players (used primarily in Europe, China and |
| some South American and African countries). |
Pixel | ' The smallest discernible element of data from a |
Pixel Phase | ' The phase of the pixel sampling clock relative to incoming data. |
Pixel Tracking | ' The frequency of the pixel sampling clock, indicated by the number of pixels per |
| line. |
Presentation Level | ' The projector is at presentation level when an image from a source is displayed |
| without the presence of a slidebar, menu, |
| ' The distance between the projector's front feet centers and the screen. Also called |
Distance | "Throw Distance”. |
Protocol | ' The type of code format called “A” or “B” utilized by the remote keypad(s). The |
| default protocol set at manufacture is Protocol “A”. By using two different keypad |
| protocols, adjacent projectors can be controlled independently with their remote IR |
| keypads. |
| ' A selectable menu item that unfolds into a list of options pertaining to it. |
Rear Screen | ' A translucent panel for screen projection. Incident light travels through the incident |
| surface of a rear screen and forms an image on the other surface. |
Resizing | ' The ability to manipulate through software commands the physical size, placement |
| and/or aspect ratio of an image. |
Resolution (lens) | ' The maximum number of alternate white and black horizontal lines that can be |
| distinguished on a screen when a photographic target is placed between the lens and a |
| light source and illuminated by that source. |
Resolution (projector) | ' The maximum number of pixels that the projector can display horizontally and |
| vertically across an image, such as 1024 x 768 (called XGA). |
Retrace Time | ' The minimum time required for a CRT projector to move the position of the scanning |
(Horizontal) | spot from the right edge to the left edge. |
Rise Time | ' The time required by the video amplifier of the projector to increase its output from |
| 10% to 90% of the maximum value. |