Auto-alignment system with focused light beam
View Patent ↗Characterizing the surface responsivity of a photo-detector includes focusing a light beam on the photo-detector surface and measuring a response of the photo-detector. The focused light beam is scanned across the surface of the photo-detector. The response of the photo-detector at each position may be recorded to allow the responsivity of the photo-detector surface to be characterized.
1. A method of characterizing a photo-detector comprising:
by an optical fiber and an optical conditioner, focusing a single light beam on the photo-detector surface;
measuring a response of the photo-detector to the focused light beam;
by a positioner that moves the optical fiber and the optical conditioner, moving the focused light beam to another position on the photo-detector surface; and
re-measuring the response of the photo-detector to the focused light beam.
2. The method of claim 1 further comprising:
repeatedly performing said moving and re-measuring; and
characterizing the responsivity of the surface of the photo-detector based on the responses.
3. The method of claim 1 including recording the responses.
4. The method of claim 3 comprising using an automated alignment system to move the light beam.
5. The method of claim 1 including generating the light beam from a stationary laser.
6. The method of claim 5 further comprising directing the light beam to the optical conditioner through a single-mode optical fiber.
7. A system for characterizing the surface of a photo-detector comprising:
a stationary light source to provide a single light beam;
an optical conditioner to focus the light beam on the surface of the photo-detector;
an optical fiber to direct the light beam from the light source to the optical conditioner; and
a positioner to move both the optical conditioner and the optical fiber so that the light beam moves across the surface of the photo-detector.
8. The system of claim 7 wherein the light source includes a laser.
9. The system of claim 7 wherein the positioner includes an automated alignment system.
10. The system of claim 9 wherein the automated alignment system includes a nano-positioner.
11. The system of claim 10 wherein the optical fiber is a single-mode optical fiber.
12. The system of claim 7 further comprising:
an output device coupled to the photo-detector to measure the output of the photo-detector; and
a display coupled to the output device.
13. A system for characterizing the surface of a photo-detector comprising:
a stationary light source to provide a single light beam;
an optical conditioner to focus the light beam on the surface of the photo-detector;
an optical fiber to direct the light from the light source to the optical conditioner;
a positioner to move the optical conditioner and the optical fiber so that the light beam moves across the surface of the photo-detector;
an output device coupled to the photo-detector to measure the output of the photo-detector; and
a display coupled to the output device.
14. The system of claim 13 wherein the light source includes a laser.
15. The system of claim 13 wherein the positioner includes an automated alignment system.
16. The system of claim 15 wherein the automated alignment system includes a nano-positioner.
17. The system of claim 1 wherein the optical fiber includes a single-mode optical fiber to direct the light beam towards the optical conditioner.