| 摘要 |
PURPOSE:To enable easy and objective testing of a photowriting head to be conducted by providing a flashing control device which makes the nth and the n+2 second microlight emitting elements simultaneously in order until a specified group is reached, and calculating an optical output from the nth and the n+1 first image sensors to measure an interval between microlight emitting elements in an array direction as well as an interval between directions at right angles with the array direction. CONSTITUTION:An image processing circuit 10 first calculates a distance Dx between LEDs 21-1, 21-3 which have emitted light. Then the circuit 10 calculates the center X1(X1a-X1b/2) of a quantity of light range X1a to X1b equal to 90% or higher of quantity of emitted light of LEDs 21-1 and the center X2(X2a-X2b/2) of quantity of light range equal to 90% or higher of quantity of emitted light of LED 21-3. After that, the circuit calculates a distance Dx between both centers based on distance Dx=¦X1-X2¦=¦(X1a+X1b)/2-(X2a+X2b)/2¦. The circuit also calculates the Y-direction in the same manner as described above, and calculates a depth of trough (h) in the Y-Y' section as the center of a distance Dy in a feeding direction. Then it is interpreted whether the optical write head 11 works satisfactorily by comparing calculation data on calculated distances Dx, Dy as well as the depth of trough (h) with previously set reference setting data. Thus it is possible to conduct the extremely easy and objective testing of the photowriting head. |
