| 摘要 |
PROBLEM TO BE SOLVED: To provide a measuring method capable of shortening measuring time of the focus of a laser beam emitting optical unit and performing focus adjustment and focus inspection in a short time. SOLUTION: Television cameras 24, 25 are arranged on two front and rear places interposing a focal position determined by optical design on the optical path of a laser beam from a laser beam transmitting optical unit 21 through a 45 deg. reflection mirror 23. First, the 45 deg. reflection mirror 23 is removed from the optical path, the emitting laser beam is measured by the television camera 24 and the peak light quantity is detected by an image processor 26. Next, the 45 deg. reflection mirror 23 is arranged on the optical path, the laser beam is introduced to/measured by the television camera 25 and the peak light quantity is similarly detected by the image processor 26. The difference of the respective peak light quantities is calculated by a host computer 27, the moving amount of a collimator lens in the unit 21 is determined based on the relation between the difference of peak light quantities and the focusing deviation calculated in advance from the optical design value of the laser beam emitting optical unit 21, a lens barrel moving unit 29 is moved through a controller 28 and focusing adjustment is finished. |
