Light source apparatus, endoscope apparatus, and light source control method

Patent metadata

Field	Value
Publication number	US-2016367124-A1
Application number	US-201615255436-A
Country	US
Kind code	A1
Filing date	Sep 2, 2016
Priority date	Mar 6, 2014
Publication date	Dec 22, 2016
Grant date	—

Abstract

A light source apparatus includes at least one light-emitter, a driving circuit, an input unit, a temperature control circuit, and an effective light power setting circuit. The driving circuit allows the light-emitter to emit light by applying a driving waveform to the light-emitter. The effective light power setting circuit drives the driving circuit to allow the light-emitter to emit light with a predetermined effective light power, in accordance with a driving condition set by the temperature control circuit. The temperature control circuit controls the light-emitter to be in a predetermined heat generation state by increasing or decreasing a heat generation amount of the light-emitter without changing the predetermined effective light power of the light emitted from the light-emitter by adjusting the driving condition of the light-emitter.

First claim

What is claimed is:

1 . A light source apparatus comprising:
at least one light-emitter configured to emit light; a driving circuit configured to apply a driving waveform to the light-emitter; an input unit configured to input a predetermined effective light power of the light emitted from the light-emitter; a temperature control circuit configured to control the light-emitter to be in a predetermined heat generation state by increasing or decreasing a heat generation amount of the light-emitter without changing the predetermined effective light power of the light emitted from the light-emitter by adjusting a driving condition of the light-emitter; and an effective light power setting circuit configured to drive the driving circuit to allow the light-emitter to emit light with the predetermined effective light power, in accordance with the driving condition adjusted by the temperature control circuit.

2 . The light source apparatus according to claim 1 , wherein
the driving waveform includes a cyclic pulse waveform, one of a peak current value of the cyclic pulse waveform and a duty cycle is set as the driving condition, and the effective light power setting circuit determines the other of the peak current value of the cyclic pulse waveform and the duty cycle, which has not been set as the driving condition, so that the effective light power of the light emitted by the light-emitter becomes the predetermined effective light power.

3 . The light source apparatus according to claim 1 , wherein
the light source includes light-emitters, the predetermined heat generation state is a state where each of the light-emitters is equal in the heat generation amount, and the temperature control circuit adjusts the driving condition so that each of the light-emitters is equal in the heat generation amount.

4 . The light source apparatus according to claim 1 , wherein
the effective light power setting circuit drives the driving circuit with the driving waveform which is continuous to allow the light-emitters to emit light in accordance with the predetermined effective light power input from the input unit, and drives a predicted heat generation amount, from driving properties of the light-emitters, when the light-emitters driven by the driving circuit emit light, and when a light-emitter of the light-emitters for which the predicted heat generation amount is greatest is set as a first light-emitter, and each light-emitter of the light-emitters which has not been set as the first light-emitter is set as a second light-emitter, the temperature control circuit sets the driving condition of the first light-emitter so that light emitting efficiency of the first light-emitter is highest.

5 . The light source apparatus according to claim 1 , further comprising at least one temperature detector which detects a temperature of the at least one light-emitter, wherein
the predetermined heat generation state is a state where the temperature of the light-emitter detected by the temperature detector is a predetermined temperature, and the temperature control circuit adjusts the driving condition so that the temperature of the light-emitter detected by the temperature detector becomes the predetermined temperature.

6 . The light source apparatus according to claim 5 , further comprising at least one temperature adjuster configured to adjust a temperature of the at least one light-emitter, wherein
a number of the at least one temperature adjuster is smaller than a number of the at least one light-emitter, the temperature detector is provided close to the first light-emitter, and the temperature control circuit drives the at least one temperature adjuster so that the first light-emitter becomes a predetermined temperature, based on the temperature of the first light-emitter detected by the temperature detector.

7 . The light source apparatus according to claim 6 , wherein
the light source includes light-emitters, and the light-emitters are arranged so that a heat conductance between each light-emitter and the temperature adjuster is equal.

8 . The light source apparatus according to claim 2 , wherein a cycle of the cyclic pulse waveform is a cycle where the at least one light-emitter is not thermally responsive.

9 . The light source apparatus according to claim 2 , wherein
the light source apparatus is combined with an imaging apparatus, and a cycle of the cyclic pulse waveform is set to be a fraction of a natural number of an image frame cycle of the imaging apparatus.

10 . The light source apparatus according to claim 1 , wherein
the light source includes light-emitters, the light source further comprises a storage configured to store driving properties of the light-emitters, and the temperature control circuit derives the driving condition based on the driving properties stored in the storage unit.

11 . An endoscope apparatus, comprising:
the light source apparatus of claim 1 ; and an image sensor configured to image a subject illuminated by light from the light source apparatus.

12 . A light source control method, comprising:
inputting a predetermined effective light power of light emitted from at least one light-emitter; setting a driving condition of the at least one light-emitter; driving a driving circuit which applies a driving waveform to the light-emitter so as to emit light with the predetermined effective light power, in accordance with the driving condition; and controlling the light-emitter to be in a predetermined heat generation state by increasing or decreasing a heat generation amount of the light-emitter without changing the predetermined effective light power of the light emitted from the light-emitter by adjusting the driving condition of the light-emitter.

Assignees

• Olympus Corp

Inventors

• Nishio Masahiro

Classifications

• A61B1/04

  combined with photographic or television appliances · CPC title

• A61B1/063 Primary

  for monochromatic or narrow-band illumination · CPC title

• H01S5/02415

  by using a thermo-electric cooler [TEC], e.g. Peltier element · CPC title

• A61B1/0661

  Endoscope light sources · CPC title

• H01S5/4025

  Array arrangements, e.g. constituted by discrete laser diodes or laser bar (H01S5/42 takes precedence) · CPC title