Stress plate optical modulator for circular dichroism measurements.
The fused silica stress plate modulator described below offers several advantages over the other known electrooptic modulation devices: primarily, high transmission over a broad wavelength range, and large aperture. When operated at its electromechanical resonance frequency of 16.7 kHz, the modulator requires only low voltage, low power drive to operate as a +/-lambda/4 plate. Complete constructional details are given, including a model from which resonance frequencies may be calculated. As part of a circular dichroism apparatus, the modulator has allowed measurement of effects as small as 1 part in 10(5). The possibility of extension of the operating range into the vacuum uv is discussed.
Mollenauer
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LF
Downie
D
D
Engstrom
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H
Grant
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WB