Television automatic geometry adjustment system

Abstract

In projection television (PTV) systems utilizing folded optical systems such as a rear projection CRT, DLP, LCD, or LCOS based televisions, or the like, an automatic geometric alignment (AGA) system including a first programmable logic, a second programmable logic operably coupled to the first programmable logic, and light sensors positioned in the over-scan region along the border of the screen and operably coupled to first programmable logic. In operation, the first programmable logic causes an on screen display (OSD) system to display and move test patterns on the screen and, using feed back data received from the light sensors, determines the geometric alignment and/or pin cushion effect error in the displayed test pattern. The second programmable logic, which includes deflection shaping circuitry to align, center or steer the beams from the projection systems, utilizes data received from the first programmable logic to compensate for geometric alignment error.