Laser driver circuit

Details Laser driver circuit Laser driver circuit

1993-12-23

1995-08-22

Scott, Jr., Leon

Coherent light generators

Particular component circuitry

Optical pumping

372 29, 372 26, H01S 300

Patent

active

054447283

ABSTRACT:
A driver circuit applies electric current to a semiconductor laser for emission of light suitable for use in a laser printer wherein a photosensitive medium is exposed by the light for imprinting an image of marks or pixels upon the medium. The current is the sum of bias current plus signal current, the latter being a sequence of pulses providing image data. The circuit includes a bypass around the laser, and the signal current is pulsed by using a switching circuit which applies a steady input current alternately to the laser and the bypass under control of a digital data signal. The switching circuit is an array of emitter-coupled logic elements operating in parallel for reduced inductance and higher switching speed. The steady input current is provided by a switching current regulator wherein a power transistor, driven by a pulse width modulator, alternately connects and disconnects current from a DC power supply in conjunction with a smoothing filter comprising an inductor and a capacitor. A current sensing resistor connects in series with the parallel circuit of laser and bypass to output a sense signal representing the amplitude of the steady input current. The sensor signal drives the pulse width modulator via a loop compensation element to establish an average value of laser current. An additional ripple current source, responsive to a high frequency component of the sensor signal, is added to the input current to counteract any ripple from the regulator.

REFERENCES:
patent: 4081670 (1978-03-01), Albanese
patent: 4237427 (1980-12-01), Holland
patent: 4347610 (1982-08-01), Meuleman
patent: 4412331 (1983-10-01), Chapman
patent: 4492970 (1985-01-01), Lee et al.
patent: 4504951 (1985-03-01), McMahan et al.
patent: 4539686 (1985-09-01), Bosch et al.
patent: 4677632 (1987-06-01), Lisco et al.
patent: 4698817 (1987-10-01), Burley
patent: 4709370 (1987-11-01), Bednarz et al.
patent: 4713672 (1987-12-01), Horihata et al.
patent: 4725854 (1988-02-01), Ohtsuka et al.
patent: 4748633 (1988-05-01), Negishi
patent: 4771431 (1988-09-01), Nakazawa et al.
patent: 4791632 (1988-12-01), Anderson et al.
patent: 4878066 (1989-10-01), Shiraishi
patent: 4886963 (1989-12-01), Ohmori
patent: 4912714 (1990-03-01), Hatanaka et al.
patent: 4916706 (1990-04-01), Ohashi
patent: 4945541 (1990-07-01), Nakayama
patent: 5123023 (1992-06-01), Santarelli et al.
patent: 5170403 (1992-12-01), Mayer
patent: 5177755 (1993-01-01), Johnson
patent: 5182756 (1993-01-01), Waki et al.
patent: 5191589 (1993-03-01), Amano et al.
patent: 5199038 (1993-03-01), Vahala et al.
patent: 5224112 (1993-06-01), Uesaka
patent: 5253267 (1993-10-01), Johnson
An Integrated Circuit for Multiplexing and Driving Injection Lasers, R. G. Swartz et al., Journal of Solid State Circuits, vol. SC-17, No. 4, Aug. 1982, pp. 753-760.
Direct Modulation of Double-Hetero-Structure Lasers at Rates up to 1 Gbit/s, M. Chown et al., Electronics Letters, Jan. 25, 1973, vol. 9, No. 2.

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