Light source device and electronic apparatus

Patent metadata

Field	Value
Publication number	US-10866375-B2
Application number	US-201916535490-A
Country	US
Kind code	B2
Filing date	Aug 8, 2019
Priority date	Aug 8, 2018
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

A light source device and an electronic apparatus are provided. The light source device includes a substrate, an electrode layer and a surrounding frame disposed on the substrate, a light emitter and a light detector mounted on the electrode layer and located inside of the surrounding frame, and a light permeable member disposed on the surrounding frame and covering the light emitter and the light detector. When the light emitter receives a predetermined current so as to emit an invisible light toward the light permeable member, the light detector receives a reflected part of the invisible light to generate an initial photocurrent. When the light emitter receives a manipulation current so that a detection photocurrent generated from the light detector is less than a first proportion of the initial photocurrent or greater than a second proportion of the initial photocurrent, the light emitter stops receiving the manipulation current.

First claim

What is claimed is:

1. A light source device, comprising:
a substrate including a first surface and a second surface opposite to the first surface;
an electrode layer disposed on the first surface of the substrate;
a surrounding frame disposed on the first surface;
a light emitter and a light detector mounted on the electrode layer and spaced apart from each other, and located on an inner side of the surrounding frame; and
a light permeable member disposed on the surrounding frame and covering the light emitter and the light detector,
wherein when the light emitter receives a predetermined current, the light emitter emits an invisible light toward the light permeable member, and the light detector receives a part of the invisible light reflected from the light permeable member so as to generate an initial photocurrent,
wherein when the light emitter receives a manipulation current so that a detection photocurrent generated from the light detector is less than a first proportion of the initial photocurrent or greater than a second proportion of the initial photocurrent, the light emitter stops receiving the manipulation current.

2. The light source device according to claim 1 , wherein the first proportion is 52.3% and the second proportion is 130.8%.

3. The light source device according to claim 1 , wherein the invisible light emitted from the light emitter passes through the light permeable member to form a first far field divergence angle along a horizontal direction and to form a second far field divergence angle along a vertical direction, and wherein the first far field divergence angle is within a range of 40-115 degrees, and the second far field divergence angle is within a range of 40-115 degrees.

4. The light source device according to claim 1 , wherein when the detection photocurrent generated from the light detector is between the first proportion and the second proportion of the initial photocurrent, the light source device satisfies Class 1 requirement of IEC 60825 standard.

5. The light source device according to claim 1 , wherein the light source device satisfies Class 1 requirement of IEC 60825 standard by having a working distance of 100 mm, an aperture of 7 mm, and a power that is less than or equal to 3.79 mW.

6. The light source device according to claim 1 , wherein the light emitter is a Vertical-Cavity Surface-Emitting Laser (VCSEL) configured to emit an infrared light.

7. The light source device according to claim 1 , wherein when the manipulation current is a direct current (DC), the manipulation current is less than 1.2 A, and a power of the light source device is equal to or less than 3.79 mW.

8. The light source device according to claim 7 , wherein the manipulation current is limited to an accessible emission limit (AEL) of the light source device with a maximum criteria limitation and a minimum criteria limitation, and wherein the light permeable member covering the light detector and the light emitter is defined as the maximum criteria limitation, the light permeable member covering the light emitter is defined as the minimum criteria limitation, and a coverage of the light permeable member under the maximum criteria limitation is greater than that under the minimum criteria limitation.

9. The light source device according to claim 8 , wherein the manipulation current is defined as x, and the detection photocurrent is defined as y, wherein in the maximum criteria limitation, the manipulation current and the detection photocurrent satisfy: y=−0.0002x 2 +1.2873x−264.86, and wherein in the minimum criteria limitation, the manipulation current and the detection photocurrent satisfy: y=−0.0001x 2 +0.7039x−178.65.

10. The light source device according to claim 1 , wherein when the manipulation current is a pulse current having a duty cycle, the manipulation current is equal to or less than 2 A, and a power of the light source device is equal to or less than 3.79 mW.

11. The light source device according to claim 10 , wherein the manipulation current is limited to an AEL of the light source device and the duty cycle both with a maximum criteria limitation and a minimum criteria limitation, and wherein the light permeable member covering the light detector and the light emitter is defined as the maximum criteria limitation, the light permeable member covering the light emitter is defined as the minimum criteria limitation, and a coverage of the light permeable member under the maximum criteria limitation is greater than that under the minimum criteria limitation.

12. The light source device according to claim 1 , wherein the light detector has a light receiving region in a rectangular shape, and a longitudinal direction of the light receiving region is perpendicular to a longitudinal direction of the surrounding frame.

13. The light source device according to claim 1 , wherein the light permeable member includes a light permeable glass board and a light-diffusing polymer layer disposed on the light permeable glass board, and the light-diffusing polymer layer faces the light emitter and the light detector.

14. The light source device according to claim 13 , wherein the light-diffusing polymer layer includes a plurality of optical microstructures facing the light emitter and the light detector, and wherein the light emitter includes a light emitting surface, and a projection area defined by orthogonally projecting the light emitting surface onto the light-diffusing polymer layer is located on an inner side of an external contour of the optical microstructures.

15. An electronic apparatus, comprising:
a light source device according to claim 1 ; and
a control unit electrically coupled to the light detector of the light source device and configured to control the manipulation current to be provided to the light emitter, wherein when the detection photocurrent generated from the light detector is less than the first proportion of the initial photocurrent or greater than the second proportion of the initial photocurrent, the light emitter stops receiving the manipulation current by the control unit.

16. A light source device, comprising:
a substrate including a first surface and a second surface opposite to the first surface;
an electrode layer disposed on the first surface of the substrate;
a surrounding frame disposed on the first surface;
a light emitter and a light detector mounted on the electrode layer and spaced apart from each other, and located on an inner side of the surrounding frame; and
a light permeable member disposed on the surrounding frame and covering the light emitter and the light detector,
wherein when the light emitter receives a predetermined current, the light emitter emits an invisible light toward the light permeable member, and the light detector receives a part of the invisible light reflected from the light permeable member so as to generate an initial photocurrent,
wherein when the light emitter receives a manipulation current so that a detection photocurrent generated from the light detector is less than a first proportion of the initial photocurrent or greater than a second proportion of the initial photocurrent, the light emitter stops receiving the manipulation current, and wherein the first proportion is 70% and the second proportion is 136%.

Assignees

• Lite On Opto Tech Changzhou Co Ltd
• Lite On Technology Corp

Inventors

• Tsai Hsin-Wei
• Chen I-Ju
• Tsao Hou-Yen
• Yang Shu-Hua
• Su Yu-Hung

Classifications

• H01S5/02257 Primary

  using windows, e.g. specially adapted for back-reflecting light to a detector inside the housing · CPC title

• H01S5/005

  Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping (H01S5/026, H01S5/18388 take precedence) · CPC title

• H01S5/02345

  Wire-bonding · CPC title

• G02B2006/4297

  having protection means, e.g. protecting humans against accidental exposure to harmful laser radiation · CPC title

• H01S5/06825

  Protecting the laser, e.g. during switch-on/off, detection of malfunctioning or degradation · CPC title