发明名称 |
Light beam intensity controlling apparatus |
摘要 |
Beam intensity controlling device includes an acoustooptic cell which receives an input light beam and produces an undiffracted or zero-order light beam and a diffracted beam in response to an RF signal at a predetermined frequency. An error signal is produced which is a function of the differences in the intensity of the zero-order beam from a desired level. This error signal is used to control the amplitude of the RF signal which in turn changes the intensity in the diffracted and zero-order beams such that the zero-order beam intensity is maintained relatively constant and can be provided as an input to a modulating device. The error signal has two components, a DC component which corrects for slow drift of the zero-order light beam intensity and an AC component which corrects for higher frequency changes in the zero-order light beam intensity.
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申请公布号 |
US4629879(A) |
申请公布日期 |
1986.12.16 |
申请号 |
US19840619453 |
申请日期 |
1984.06.11 |
申请人 |
EASTMAN KODAK COMPANY |
发明人 |
BALDWIN, ROGER E.;WOO, NEA-YEA |
分类号 |
G02F1/11;(IPC1-7):G01J1/32;G01R27/02 |
主分类号 |
G02F1/11 |
代理机构 |
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