Optical Trap Detector with Large Acceptance Angle

• Published in: Journal of Light & Visual Environment Vol. 32; no. 3; pp. 295 - 301
• Main Authors: ICHINO, Yoshiro, SAITO, Terubumi, SAITO, Ichiro
• Format: Journal Article
• Language: English
• Published: Tokyo The Illuminating Engineering Institute of Japan 01.01.2008; Japan Science and Technology Agency
• Subjects: acceptance angle; silicon photodiode; spectral responsivity; trap detector
• ISSN: 0387-8805; 1349-8398
• DOI: 10.2150/jlve.32.295

We have developed a polarization-independent reflection-type silicon photodiode trap detector and characterized its performance by laser beam-based measurement. Three dimensional CAD-based modeling enables us to optimize its interior design, resulting in minimizing each distance between centers of adjacent photodiodes by rotating each photodiode by 45° along each normal axis. It is expected by a simple ray-tracing simulation and also confirmed experimentally that the trap detector incorporating a photodiode with a large active area exhibits the largest acceptance angle ever proposed as the polarization-independent trap detector for the convergent incident beam. This is suitable for the national standard detector to realize and disseminate the cryogenic radiometer-based spectral power responsivity with high accuracy. It is also applicable to various kinds of working or transfer standard detectors for collimated or non-collimated monochromatic radiation. In addition, a history of development of trap detectors at national laboratories is reviewed.