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Term (Acronym) [units]: Definition

Radio Frequency Interference (RFI): Electromagnetic radiation that is emitted by electronic circuits carrying rapidly changing signals as a byproduct of normal operation, and which causes unwanted signals (interference or noise) to be induced in other circuits, thus limiting their performance. Also called EMI.

Rear Projection Television (RPTV): A television that projects the image from a microdisplay onto the rear of a high-gain screen. RPTVs are made with three different microdisplay technologies: DLP, HTPS-LCD and LCoS. RPTVs were previously made with small (5-inch) CRTs, but this technology has become obsolete. RPTVs are also called Microdisplay TVs (MDTVs or MD-RPTVs).

RGB (Red, Green and Blue): In this additive color model the three primary colors of the light are mixed in varying intensities to create the entire visible spectrum. LCDs use individual RGB pixel elements (subpixels) to create a single white pixel.

Reflective LCD: A type of LCD where the image is illuminated entirely by light reflected from the surface of the pixels (there is no backlight). The light source can either be ambient light or a frontlight.

Refresh Rate: Applicable only to CRTs and not LCDs, the refresh rate is the number of times per second that the electron gun redraws the image on the screen.

Resistive Touch: An analog touch screen technology that uses the contact point of two transparent conductive films to locate the user’s touch point within the active area.

Resolution: Resolution has two distinct and related meanings. In the general media, resolution is the number of pixels displayed on a flat-panel display, usually expressed as the number of horizontal pixels by the number of vertical pixels (e.g., 1024x768). In more technical media, resolution refers to the number of pixels per inch. Higher-resolution displays have more pixels per inch, even though the total number of pixels in the display may be the same as in a lower-resolution display.

Response Time: A measure of how quickly an LCD can display a change in the brightness of the screen image. It’s calculated as the sum of the times needed for the image to change from 10% to 90% of its maximum brightness, and from 90% to 10%. Faster response times enable a smoother display of rapidly changing screen images, although it’s not the only factor that controls the smoothness.

Retardation Film: A film that changes (delays) the phase of a light wave. When linearly polarized light is put through a retardation film, it changes to circularly polarized light.

Return-On-Investment (ROI): The earnings-to-investment ratio of a project, expressed as a percentage.

Rotation: Swiveling a display 90 degrees to change from landscape mode to portrait mode or vice-versa.

Row: A horizontal line of pixels.

Rubbing: A step in the LCD manufacturing process in which a cloth is rubbed repeatedly against the alignment layer in the LCD in order to align the liquid crystal molecules parallel to the rubbing direction. Also called "buffing".

Ruggedization: The process of making a display more resistant to conditions in the environment that could damage it, such as high & low temperatures, shock, vibration, drop, high and low humidity, ultraviolet light, etc.