Abstract A repetitive voltage signal, such as a sinusoidal wave, is supplied to the anode of a step-recovery diode through an inductor. A variable voltage source is connected to the cathode of the step-recovery diode. Conduction of the step-recovery diode and cut-off of the reverse current flowing through it are repeated with a period identical to the period of the repetitive voltage signal. On account of the abrupt reverse current cut-off characteristic of the step-recovery diode, a voltage is induced in the inductor when the reverse current is cut off, thereby producing an abrupt voltage change at the junction point between the inductor and the step-recovery diode. This abrupt voltage change is converted by differentiation into a short pulse to drive a semiconductor laser diode.
Inventors
👤 Akira Takahashi
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-02 12:32
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/04; H01S5/042
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
125 words
A device for driving a light source, comprising: means for generating a repetitive sinusoidal input voltage signal having a frequency; means for modifying said repetitive sinusoidal input voltage signal to a modified voltage signal having an abrupt transient voltage change, the modifying means including: inductor means coupled to said generating means, voltage source means for providing a bias voltage, and step recovery diode means coupled between the voltage source means and the inductor means for producing said modified voltage signal; means coupled to said modifying means for differentiating the modified voltage signal to produce a repetitive pulse voltage signal having a frequency corresponding to the frequence of the sinusoidal input voltage signal; and means for providing said pulse voltage signal to drive said light source.
Claim 2
Independent Claim
125 words
A device for driving a light source, comprising: means for generating a repetitive sinusoidal input voltage signal having a frequency; means for modifying said repetitive sinusoidal input voltage signal to a modified voltage signal having an abrupt transient voltage change, the modifying means including: inductor means coupled to said generating means, voltage source means for providing a bias voltage, and step recovery diode means coupled between the voltage source means and the inductor means for producing said modified voltage signal; means coupled to said modifying means for differentiating the modified voltage signal to produce a repetitive pulse voltage signal having a frequency corresponding to the frequence of the sinusoidal input voltage signal; and means for providing said pulse voltage signal to drive said light source.
Claim 3
Dependent Claim
18 words
The light source drive device according to claim 1, wherein the light source is a semiconductor light-emitting element.
Claim 4
Dependent Claim
18 words
The light source drive device according to claim 2, wherein the semiconductor light-emitter element is a laser diode.
Claim 5
Dependent Claim
23 words
The light source driving device according to claim 1, further comprising means coupled to the light source for providing a bias current thereto.