PURPOSE: To set an optimum operating temperature in a short time by a simple operation without requiring special apparatus and facilities by mounting a display section displaying the temperature of a point where projecting power crosses at an acceptable variation level by comparing comparison means.
CONSTITUTION: The projecting power from a laser diode 30a is received by a photosensor 34, and inputted to a comparison section 40 through an optical power meter 35, and an optical power signal and allowable voltage VL∼VH are compared. A CPU39 adjusts a temperature in a semiconductor laser package 30 to +ΔT through a set-temperature adjusting section 42, and the temperature is compared by the comparison section 40. The process is repeated, an output from the comparison section 40 is triggered at an intersecting point where the optical power signal projects from the range of allowable voltage VL∼VH, and a temperature at that time is memorized to a memory 41. When the temperature reaches to an upper limit TE within the range of an operating temperature, a temperature at a trigger point is displayed to a display section 43 while only a widest temperature range Ti∼Tj is flickered and displayed. An optimum set temperature is represented by a temperature close to (Ti+Tj)/2.
| JPH077221 | SEMICONDUCTOR LASER ELEMENT |
| JP4155834 | Semiconductor laser |
| JPH0599739 | PHOTODETECTOR |
KITAJIMA HIROSHI
MORISHITA KOUJI
NAKATSUKA NOBUO
Next Patent: SETTER FOR OPERATING TEMPERATURE OF SEMICONDUCTOR LASER