OPTICAL ARRANGEMENT FOR CAMERA MODULES, CAMERA MODULES WITH OPTICAL ARRANGEMENTS, AND METHOD OF MANUFACTURE

• US 20170219749A1
• Filed: 04/20/2017
• Published: 08/03/2017
• Est. Priority Date: 10/20/2014
• Status: Active Grant

• Current Assignee: Schott Glass Technologies Suzhou Co Ltd
• Original Assignee: Schott Glass Technologies Suzhou Co Ltd
• Inventors: HOU, Dengke, CHEN, Fan, BIERTUEMPFEL, Ralf
• Granted Patent: US 10,416,365 B2
• Time in Patent Office: Days
• CPC Class Codes: B29D 11/00634 Production of filters
• CPC Class Codes: B29D 11/0073 Optical laminates
• CPC Class Codes: B29K 2995/0026 Transparent
• CPC Class Codes: G02B 1/02 made of crystals, e.g. rock-salt, semi-conductors G02B1/08 takes precedence
• CPC Class Codes: G02B 1/11 Anti-reflection coatings
• CPC Class Codes: G02B 3/00 Simple or compound lenses
• CPC Class Codes: G02B 5/208 for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation
• CPC Class Codes: G02B 5/223 containing organic substances, e.g. dyes, inks or pigments
• CPC Class Codes: G02B 5/226 Glass filters
• CPC Class Codes: G02B 5/26 Reflecting filters G02B5/28 takes precedence
• CPC Class Codes: G02B 5/282 reflecting for infrared and transparent for visible light, e.g. heat reflectors, laser protection
• CPC Class Codes: G03B 11/00 Filters or other obturators specially adapted for photographic purposes

Abstract

An optical arrangement for a camera module with an image sensor is provided. The optical arrangement includes optical components having a transparent cover element; an infrared absorbing cut-off filter; and an optical lens. The optical components are arranged, along an incident optical beam path going through the optical components onto the image sensor, in a sequence through the transparent cover element, then the infrared absorbing cut-off filter, and then the optical lens.

Claims

1. An optical arrangement for a camera module with an image sensor, comprising a plurality of optical components having an incident optical beam path towards the image sensor, the plurality of optical components comprising a transparent cover element, an infrared absorbing cut-off filter, and an optical lens, the plurality of optical components being arranged, along the incident optical beam, in a sequence from the cover element to the cut-off filter, and then to the optical lens.

2. The optical arrangement according to claim 1, wherein the cover element is formed as a sheet made of a material selected from the group consisting of sapphire, chemically strengthened glass, spinel, aluminium oxynitride, moissanite, corundum, and quartz.

3. The optical arrangement according to claim 1, wherein the cut-off filter is formed as an infrared absorbing filter glass element.

4. The optical arrangement according to claim 3, wherein the infrared absorbing filter glass element comprises a filter glass sheet or substrate.

5. The optical arrangement according to claim 4, wherein the infrared absorbing filter glass element comprises blue glass or an infrared absorbing layer made of an organic ink or organic film.

6. The optical arrangement according to claim 1, wherein the cut-off filter and the cover element are combined to a protective IR filter.

7. The optical arrangement according to claim 6, wherein the protective IR filter is composed of a filter film on a rear face of the cover element.

8. The optical arrangement according to claim 7, wherein the filter film is a two-layered material formed as a laminate material or as a coated material.

9. The optical arrangement according to claim 6, wherein the protective IR filter comprises an IR reflecting layer.

10. The optical arrangement according to claim 9, wherein the IR reflecting layer is arranged on one face of the cover element or on one face of the cut-off filter.

11. The optical arrangement according to claim 6, wherein the protective IR filter comprises an antireflection layer arranged on one face of the cover element or on one face of the cut-off filter.

12. The optical arrangement according to claim 6, wherein the protective IR filter comprises a hybrid IR reflecting and antireflection layer arranged on one face of the cover element or on one face of the cut-off filter.

13. The optical arrangement according to claim 1, further comprising an antireflection layer coated on a front face and/or on a rear face of the cover element.

14. The optical arrangement according to claim 1, wherein the cut-off filter has a thickness of less than 0.3 mm.

15. The optical arrangement according to claim 1, wherein the cover element and the cut-off filter are cemented together.

16. A camera module comprising the optical arrangement according to claim 1.

17. The camera module according to claim 16, wherein the optical lens is an objective lens having a minimum back focal length of 3.6 mm.

18. A method of manufacturing an optical arrangement for a camera module with an image sensor, the method comprising:

providing a transparent cover element made of a chemically strengthened glass or sapphire;

producing a protective IR filter by adding an infrared absorbing cut-off filter to the cover element, the infrared absorbing cut-off filter covering a rear face of the cover element;

providing a lens or lens assembly; and

arranging, along an incident optical beam path going onto the image sensor, the lens assembly at a position between the protective IR filter and the image sensor, a front face of the cover element, which is opposed to the rear face, being exposed to the incident optical beam.

19. The method according to claim 18, wherein the step of producing the protective IR filter is performed by laminating or coating the cover element with the infrared absorbing cut-off filter.

20. The method according to claim 19, further comprising the step of producing the IR reflecting coating on a face of the cover element, before or after, laminating the cover element with the infrared absorbing cut-off filter.

21. The method according to claim 18, further comprising the step of producing an antireflection coating and/or an IR reflecting coating or a hybrid IR reflecting and antireflection coating on the front face of the cover element.

22. The method according to claim 18, further comprising the step of producing an antireflection coating or a hybrid IR reflecting and antireflection coating on the rear face of the infrared absorbing cut-off filter.