Laser output power stabilization for direct laser writing system by using an acousto-optic modulator.
We present experimental results on the output power stabilization of an Ar(+) laser for a direct laser writing system (LWS). Instability of the laser output power in the LWS cause resolution fluctuations of being fabricated diffractive optical elements or computer-generated holograms. For the purpose of reducing the power fluctuations, we have constituted a feedback loop with an acousto-optic modulator, a photodetector, and a servo controller. In this system, we have achieved the stability of +/-0.20% for 12 min and the relative intensity noise level of 2.1 x 10(-7) Hz(-12) at 100 Hz. In addition, we applied our system to a 2 mW internal mirror He-Ne laser. As a consequence, we achieved the output power stability of +/-0.12% for 25 min.
Kim
Dong Ik
DI
Space Optics Research Center, Korea Research Institute of Standards and Science, 1 Doryong-Dong, Yuseong-Gu, Daejeon 305-340, Republic of Korea.
Rhee
Hyug-Gyo
HG
Song
Jae-Bong
JB
Lee
Yun-Woo
YW
D000162:Acoustics; D004581:Electronics / Q000295:instrumentation*; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D055095:Optics and Photonics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*