Laser Light Source Device Positional Deviation Detection

Solution Overview

Problem

Existing high-power laser light source devices that employ wavelength beam combining suffer from partial output light loss due to the need for monitoring a portion of the combined light beam to detect positional deviations.

Innovation Solution

A light source device that includes a plurality of laser light sources, collimating lenses, a first transmission diffraction grating for combining light beams, and a sensor to detect positional deviations in diffracted light without affecting the combined light, allowing for positional deviation detection without branching the output light.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a portion of the combined light beam is branched for monitoring, then positional deviation can be detected, but output light is partially lost

Engineering Contradiction:

Improvepositional deviation detectionVSAvoidoutput light loss

Core Design Contradiction:

Measurement precisionVSLoss of energy

Solution Approach 1:

A beam splitter is introduced as an intermediary component to separate a portion of the combined light beam for monitoring purposes. The beam splitter directs most of the light (e.g., 90%) to the output while directing a small portion (e.g., 10%) to the position detection device, enabling positional deviation detection without significant loss of output light.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

Instead of directly monitoring the main light beam which would cause energy loss, a copy or portion of the beam is created using the beam splitter. This copied beam is then used for position detection, allowing the main beam to continue to its destination with minimal interruption or energy loss.

Inventive Principle:

Principle #26Copying

2Measurement precision

If monitoring devices are added to detect positional deviation, then detection capability is improved, but device complexity and cost increase

Engineering Contradiction:

Improvepositional deviation detectionVSAvoidmonitoring device structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

A beam splitter is introduced as an intermediary component to separate a portion of the combined light beam for monitoring purposes. The beam splitter directs most of the light (e.g., 90%) to the output while directing a small portion (e.g., 10%) to the position detection device, enabling positional deviation detection without significant loss of output light.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

Instead of directly monitoring the main light beam which would cause energy loss, a copy or portion of the beam is created using the beam splitter. This copied beam is then used for position detection, allowing the main beam to continue to its destination with minimal interruption or energy loss.

Inventive Principle:

Principle #26Copying

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables detection of positional deviations in combined light without reducing the output light quality, reducing the need for expensive monitoring devices and minimizing light absorption, thus maintaining high-power laser performance while simplifying the device structure and reducing costs.

Implementation Method 1

collimating lenses each configured to collimate the light beam emitted from a corresponding one of the laser light sources so as to be substantially parallel to an optical axis of the laser light source

Methodology Applied

Scientific EffectCollimation: Lens

Implementation Method 2

a first transmission diffraction grating configured to diffract and combine, in an identical diffraction angle direction, the light beams transmitted through corresponding ones of the collimating lenses and incident on a single region at different incident angles

Methodology Applied

Scientific EffectDiffraction: Diffraction

Implementation Method 3

a sensor configured to detect a positional deviation in diffracted light beams that are diffracted and combined by the first transmission diffraction grating

Methodology Applied

Scientific EffectPhotoelectric detection: Photoelectric Effect

Data Source

PatentUS10998698B2Light source device

Publication Date: 2021.05.04 NICHIA CORP

AI summary

A light source device includes: a plurality of laser light sources, each configured to emit a light beam; a plurality of collimating lenses, each configured to collimate the light beam emitted from a corresponding one of the laser light sources; a first transmission diffraction grating configured to diffract and combine, in an identical diffraction angle direction, the light beams transmitted through the collimating lenses and incident on a single region at different incident angles; a sensor configured to detect a positional deviation in diffracted light beams that are diffracted and combined by the first transmission diffraction grating; and a plurality of wavelength selecting elements, each disposed on an optical path between a respective one of the collimating lenses and the first transmission diffraction grating and configured to select a wavelength of a corresponding one of the light beams incident on the first transmission diffraction grating.