CATalignmentdefinitionandcalculatio.docVIP

CAT alignment definition and calculation 1. X-position: define X-axis position related carriage and CCD. Calculation method: Find out the center point of 7th and 8th black stripe of alignment target in CCD pixels. 7th center point pixels + 8th center point pixels/2=X position. 2. Y-position: define Y-axis position related carriage and CCD. This position is optical center of slot. Alignment method: a. Find out the R(RED) and B(BLUE) bounce which is project to CAT alignment chart. Then use below calculation method to find out Y position. b. The R,B bounce come out condition: R/B or B/R response ratio is 1/3. G response must over 80. Calculation method: Slant black strip on alignment target is 45°. Find out the center point of 2nd black strip in CCD pixels. Find out the center point of 3rd (slant) black strip in CCD pixels Find out the center point of 12th (slant) black strip in CCD pixels Find out the center point of 13th black strip in CCD pixel A= 3rd center pixels –2nd center pixels B= 13th center pixels – 12th center pixels A+B/2= Y position. Need to get R,B Y position, then Ry+By/2= Y position (final) Generate the limit area by alignment program. Operator must align into this area, otherwise the green light can’t be showed. 3. Z-position: Magnification. Calculation method: Get image length from 1st black strip center to 14th black strip center. Total length (pixels) divide by real length. 4. Y-angle: Distortion for each segment. Calculation: a. Get image length from 1st black strip center to 2nd black strip center. b. Above (1st to 2nd) image length divide by real length. 5. Z-angle: The slant degree of reading line. Calculation method: Refer Y position calculation method from a step to g step. A-B= Z angle. 6. X-Response: CCD output response. Calculation method: a. Get each segment CCD response, M