Optical module for preventing cross talk due to undesirable refection light, manufacturing process thereof and electronic device comprising the same

• US 10,121,918 B2
• Filed: 07/09/2015
• Issued: 11/06/2018
• Est. Priority Date: 07/09/2014
• Status: Active Grant

• Current Assignee: Advanced Semiconductor Engineering Inc (ASE Technology Holding Co., Ltd.)
• Original Assignee: Advanced Semiconductor Engineering Inc (ASE Technology Holding Co., Ltd.)
• Inventors: Chang, Jung-Hsuan, Chen, Ying-Chung
• Primary Examiner(s): Whalen, Daniel
• Application Number:
  US14/795,613
• Publication Number:
  US 20160013223A1
• Time in Patent Office: 1,216 Days
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 7/4813 Housing arrangements
• CPC Class Codes: G01S 7/499 using polarisation effects
• CPC Class Codes: H01L 27/1446 in a repetitive configuration
• CPC Class Codes: H01L 31/0232 Optical elements or arrangements associated with the device H01L31/0236 takes precedence; for photovoltaic cells H01L31/054; for photovoltaic modules H02S40/20
• CPC Class Codes: H01L 31/02327 the optical elements being integrated or being directly associated to the device, e.g. back reflectors optical coatings H01L31/0216
• CPC Class Codes: H01L 31/173 formed in, or on, a common substrate
• CPC Class Codes: H01L 31/18 Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
• CPC Class Codes: H01S 5/18355 having a defined polarisation
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

The present disclosure relates to an optical module. In an embodiment, the optical module includes a carrier, a light source, a light detector, and a first polarizer. The light source and the light detector are disposed adjacent to a first surface of the carrier. The first polarizer is disposed on the light detector. The optical module is configured to polarize light emitted from the light source into a first polarization direction substantially perpendicular to a second polarization direction of light permitted through the first polarizer.

Claims

1. An electronic device, comprising:

a carrier having a first surface;

a light source disposed adjacent to the first surface;

a light detector disposed adjacent to the first surface;

a first polarizer disposed on the light detector, wherein light emitted from the light source has a first polarization direction substantially perpendicular to a second polarization direction of light permitted through the first polarizer; and

a transparent sheet, having a first surface and a second surface opposite to the first surface, the first surface of the transparent sheet facing the first surface of the carrier, the second surface of the transparent sheet comprising a waveplate configured to transform the light emitted from the light source and passing through the waveplate into light having a different polarization state.

2. The electronic device of claim 1, wherein the waveplate comprises a ¼

λ

waveplate.

3. The electronic device of claim 1, wherein the light emitted from the light source has a linear polarization and the waveplate is configured to transform the light emitted from the light source and passing through the waveplate into light having a circular polarization.

4. The electronic device of claim 1, wherein the waveplate is configured to transform reflected light having a circular polarization and passing through the waveplate into light having a linear polarization.

5. The electronic device of claim 1, wherein the light source comprises a vertical-cavity surface-emitting laser.

6. The electronic device of claim 1, wherein the light detector comprises one or more photosensitive areas, and the first polarizer covers at least one photosensitive area.

7. The electronic device of claim 1, wherein the light detector comprises a photosensitive area, and the first polarizer covers substantially all of the photosensitive area.

8. The electronic device of claim 1, further comprising a second polarizer disposed on the light source, wherein the second polarizer is configured to polarize the light emitted from the light source into the first polarization direction.

9. The electronic device of claim 1, wherein the light source comprises one or more light emitting areas, and the second polarizer covers at least one light emitting area.

10. A process of manufacturing an optical module, comprising:

providing a carrier, the carrier having a first surface;

disposing a light source structure adjacent to the first surface, the light source structure configured to emit light in a first polarization direction;

disposing a light detection structure adjacent to the first surface, the light detection structure configured to admit light in a second polarization direction, wherein the first polarization direction is substantially perpendicular to the second polarization direction; and

disposing a transparent sheet above the light source structure and the light detection structure, the transparent sheet having a first surface and a second surface opposite to the first surface, the first surface of the transparent sheet facing the first surface of the carrier, the second surface of the transparent sheet comprising a waveplate configured to transform the light emitted from the light source structure and passing through the waveplate into light having a different polarization state.

11. The process of claim 10, wherein the light source structure comprises a light source and a first polarizer, and disposing the light source structure comprises disposing the light source adjacent to the first surface and disposing the first polarizer on the light source.

12. The process of claim 11, wherein the light source comprises one or more light emitting areas, and the first polarizer covers at least one light emitting area.

13. The process of claim 11, wherein the light detection structure comprises a light detector and a second polarizer, and disposing the light detection structure comprises disposing the light detector adjacent to the first surface and disposing the second polarizer on the light detector, and wherein the light detector comprises at least one photosensitive area, and the second polarizer is disposed adjacent to the at least one photosensitive area.

14. An electronic device, comprising:

a light source;

a light detector;

an enclosure encapsulating the light source and the light detector;

a waveplate configured to cover the light source and the light detector such that a first light beam emitted from the light source passes through the waveplate and reaches an object, and the first light beam reflected by the object passes through the waveplate and reaches the light detector; and

a transparent sheet, having a first surface and a second surface opposite to the first surface, the first surface of the transparent sheet facing the light source, wherein the waveplate is disposed adjacent to one of the first surface or the second surface of the transparent sheet.

15. The electronic device of claim 14, further comprising a polarizer disposed on the light detector, wherein the first light beam emitted from the light source has a first polarization direction substantially perpendicular to a second polarization direction of light permitted through the polarizer.

16. The electronic device of claim 14, wherein the waveplate comprises a ¼

λ

waveplate.

17. The electronic device of claim 14, wherein the light source is a vertical-cavity surface-emitting laser.

18. The electronic device of claim 14, wherein the waveplate is disposed outside of the enclosure.

19. The electronic device of claim 14, wherein the waveplate is configured to transform the first light beam emitted from the light source in a first polarization state into a second polarization state and to transform the first light beam reflected from the object in a third polarization state into a fourth polarization state.

20. The electronic device of claim 19, wherein the first polarization state has a linear polarization, and the second polarization state has a circular polarization.

21. The electronic device of claim 19, wherein the third polarization state has a circular polarization, and the fourth polarization state has a linear polarization.

22. The electronic device of claim 19, wherein light in the fourth polarization state has a polarization direction substantially perpendicular to a polarization direction of light in the first polarization state.

23. The electronic device of claim 19, further comprising a polarizer disposed on the light source, wherein the polarizer is configured to polarize the first light beam emitted from the light source into the first polarization state.