摘要 |
The dynamic range of a continuous tone laser printer is extended by directly modulating a diode laser while simultaneously modulating the optical output of the diode laser with an acousto-optic modulator. The digital image value is input to two look-up tables (LUTs) that convert the image value to two digital words; one to set the power level of the diode laser, and the other to set the diffraction efficiency of the acousto-optic modulator (AOM). The first look-up table is constructed from the performance characteristics of the diode laser, and the second look-up table is constructed from the performance characteristics of the AOM. The look-up table digital outputs are applied to respective digital to analog converters whose analog outputs respectively drive a voltage to current driver for the diode laser and a radio frequency dirver for the AOM. The resulting power of the writing laser beam is a linear function of the input image value.
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