Sensor device having an integral anamorphic lens

• US 20020056806A1
• Filed: 01/10/2002
• Published: 05/16/2002
• Est. Priority Date: 01/25/1999
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Roberts, John K., Bechtel, Jon H., Ockerse, Harold C.
• Granted Patent: US 6,679,608 B2
• Time in Patent Office: Days
• US Class Current: 250/214.1
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: G01J 1/0266 Field-of-view determination; Aiming or pointing of a photometer; Adjusting alignment; Encoding angular position; Size of the measurement area; Position tracking; Photodetection involving different fields of view for a single detector
• CPC Class Codes: G01J 1/0271 Housings; Attachments or accessories for photometers
• CPC Class Codes: G01J 1/04 Optical or mechanical part supplementary adjustable parts
• CPC Class Codes: G01J 1/0411 using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
• CPC Class Codes: G01J 1/42 using electric radiation detectors optical or mechanical part G01J1/04; by comparison with a reference light or electric value G01J1/10
• CPC Class Codes: G01J 1/46 using a capacitor
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0076 for use with a detector G02B19/009, G02B19/0095 take precedence
• CPC Class Codes: G02B 5/021 the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures
• CPC Class Codes: G02B 5/0215 the surface having a regular structure
• CPC Class Codes: G02B 5/0221 the surface having an irregular structure G02B5/0226 takes precedence
• CPC Class Codes: G02B 5/0242 by means of dispersed particles
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details

Abstract

The inventive sensor device provides different fields of view in transverse directions. The sensor device include a support structure, a sensing element mounted on the support substrate for sensing optical radiation and generating an electrical output signal in response thereto, and an encapsulant encapsulating the sensing element on the support structure. The encapsulant includes an integral anamorphic lens. Alternatively or additionally, the encapsulant may have at least a first zone and a second zone, where the second zone exhibits at least one different characteristic from the first zone, such as a different optical, physical, thermal, or compositional characteristic.

Claims

1. A sensor device comprising:

a support structure;

a sensing element mounted on said support substrate for sensing optical radiation and generating an electrical output signal in response thereto; and

an encapsulant encapsulating said sensing element on said support structure, said encapsulant including an integral anamorphic lens.

2. The sensor device of claim 1, wherein said support structure is a portion of a lead frame.

3. The sensor device of claim 2, wherein said portion of the lead frame includes at least two leads electrically coupled to said sensing element, and wherein said leads are retained by said encapsulant.

4. The sensor device of claim 1, wherein said integral anamorphic lens is a bi-radial lens.

5. The sensor device of claim 4, wherein said bi-radial lens is a toric lens.

6. The sensor device of claim 1, wherein said integral anamorphic lens is a cylindrical lens.

7. The sensor device of claim 1, wherein said integral anamorphic lens presents different fields of view to said sensing element for transverse directions.

8. The sensor device of claim 1 and further comprising a diffusant dispersed throughout at least a portion of said encapsulant.

9. The sensor device of claim 1, wherein said sensing element is sensitive to visible light.

10. The sensor device of claim 1, wherein said integral anamorphic lens has different focal lengths for transverse directions

11. The sensor device of claim 10, wherein a sensing area of said sensing element is positioned closer to the surface of said integral anamorphic lens than either focal length of said integral anamorphic lens.

12. The sensor device of claim 1, wherein said sensing element comprises:

a light transducer exposed to light, the light transducer operative to accumulate charge in proportion to light incident over an integration period; and

a sensor logic circuit in communication with the exposed light transducer, the sensor logic circuit operative to output a discrete light signal according to the accumulated exposed light transducer charge.

13. The sensor device of claim 12, wherein said sensing element further comprises:

a shielded light transducer shielded from ambient light, the shielded light transducer operative to accumulate charge in proportion to noise over the integration period, and wherein the sensor logic circuit is further operative to output the discrete light signal based on the difference between the measured accumulated exposed light transducer charge and the measured accumulated shielded light transducer charge.

14. The sensor device of claim 12, wherein said integration period is variable in response to a received integration signal.

15. The sensor device of claim 12, wherein the integration period is of a length of time that is predetermined prior to accumulation of charge during the integration period.

16. The sensor device of claim 1, wherein said encapsulant has at least a first zone and a second zone, the second zone exhibiting at least one different characteristic from the first zone.

17. The sensor device of claim 1, wherein said sensing element has an active sensing area less than 1 mm².

19. The sensor device of claim 18, wherein said lens has different focal lengths in transverse directions.

20. The sensor device of claim 18, wherein said lens has an anamorphic surface.

21. The sensor device of claim 20, wherein said anamorphic surface is bi-radial.

22. The sensor device of claim 21, wherein said bi-radial surface is toric.

23. The sensor device of claim 20, wherein said anamorphic surface is cylindrical.

24. The sensor device of claim 18, wherein said support structure is a lead frame having at least first and second electrical leads electrically coupled to said sensing element.

25. The sensor device of claim 24, wherein said sensing element is mounted on one of said first and second electrical leads.

26. The sensor device of claim 25 and further including a wire bond extending from one of said first and second electrical leads to said sensing element.

27. The sensor device of claim 18, wherein said sensing element has an active sensing area less than 1 mm².

29. The vehicle accessory of claim 28, wherein the vehicle accessory is a rearview mirror assembly.

30. The vehicle accessory of claim 29, wherein mirror is an electrochromic mirror.

31. The vehicle accessory of claim 30 and further comprising a processing circuit coupled to said sensor device for controlling said electrochromic mirror in response to light levels sensed by said sensing element.

32. The vehicle accessory of claim 31, wherein said sensor device is aimed forward of the vehicle for sensing ambient light levels.

33. The vehicle accessory of claim 31, wherein said sensor device is aimed rearward of the vehicle for sensing glare.

34. The vehicle accessory of claim 31 and further comprising a second sensor device for sensing light levels from sources in a different field of view from the first sensor device.

35. The vehicle accessory of claim 34, wherein said second sensor device comprises:

a support structure;

a sensing element mounted on the support structure for sensing optical radiation and generating an electrical output in response thereto; and

an encapsulant encapsulating said sensing element on said support structure, said encapsulant including an integral anamorphic lens.

36. The vehicle accessory of claim 31, wherein said processing circuit is further configured to generate light control signals to control at least one vehicle light in response to light levels sensed by said sensing element.

37. The vehicle accessory of claim 29 and further comprising a processing circuit coupled to said sensor device for generating light control signals to control at least one vehicle light in response to light levels sensed by said sensing element.

38. The vehicle accessory of claim 28 and further comprising a processing circuit coupled to said sensor device for generating light control signals to control at least one vehicle light in response to light levels sensed by said sensing element.

39. The vehicle accessory of claim 38, wherein said at least one vehicle light includes vehicle headlamps and said processing circuit controls the on/off state of the vehicle headlamps.

40. The vehicle accessory of claim 38, wherein said at least one vehicle light includes interior display lights.

41. The vehicle accessory of claim 28 and further comprising a processing circuit coupled to said sensor device for generating windshield wiper control signals to control windshield wipers of the vehicle in response to light levels sensed by said sensing element.

42. The vehicle accessory of claim 28 and further comprising a processing circuit coupled to said sensor device for generating climate control signals to control a climate control system of the vehicle in response to light levels sensed by said sensing element.

43. The vehicle accessory of claim 42, wherein said sensor device is positioned to sense sun loading on the vehicle.

44. The vehicle accessory of claim 28, wherein said sensing element has an active sensing area of less than 1 mm².

46. The sensor device of claim 45, wherein said lens has different focal lengths for transverse directions.

47. The sensor device of claim 45, wherein said lens is anamorphic.

48. The sensor device of claim 45, wherein said support structure is a lead frame.

50. The sensor device of claim 49, wherein said at least one different characteristic is a physical characteristic.

51. The sensor device of claim 49, wherein said at least one different characteristic is an optical characteristic.

52. The sensor device of claim 51, wherein said at least one different optical characteristic is transparency.

53. The sensor device of claim 51, wherein said at least one different optical characteristic is diffusivity.

54. The sensor device of claim 49, wherein said at least one different characteristic is a thermal characteristic.

55. The sensor device of claim 49, wherein said at least one different characteristic is a structural characteristic.

56. The sensor device of claim 55, wherein said at least one different characteristic includes at least one of tensile strength and compression strength.

57. The sensor device of claim 49, wherein said at least one different characteristic is a compositional characteristic.

58. The sensor device of claim 49, wherein the at least one different characteristic includes at least one of the following:

mechanical strength, thermal conductivity, thermal capacity, specific heat, coefficient of thermal expansion, adhesion, oxygen impermeability, moisture impermeability, and transmittance for radiation emitted from said radiation emitter.

59. The sensor device of claim 49, wherein a region of said first zone of said encapsulant is configured to function as a lens.

60. The sensor device of claim 49, wherein said second zone of said encapsulant is configured to retain electrical leads of said support structure.

61. The sensor device of claim 49, wherein said first zone of said encapsulant is optically transparent and extends from said sensing element to a light input surface of said encapsulant.

62. The sensor device of claim 49, wherein said second zone has a lower thermal resistance than said first zone.

63. The sensor device of claim 49, wherein said second zone has a higher thermal capacity than said first zone.

64. The sensor device of claim 49, wherein said second zone has a greater mechanical strength than said first zone.

65. The sensor device of claim 49, wherein said second zone has a lower coefficient of thermal expansion than said first zone.

66. The sensor device of claim 49, wherein said second zone has a greater adhesion strength than said first zone.

67. The sensor device of claim 49, wherein said second zone has lower oxygen permeability than said first zone.

68. The sensor device of claim 49, wherein said second zone has lower moisture permeability than said first zone.

69. The sensor device of claim 49, wherein said encapsulant includes an integral anamorphic lens for directing incident optical radiation toward said sensing element.

70. The sensor device of claim 49, wherein said sensing element has an active sensing area of less than 1 mm².

18. A sensor device comprising:

a support structure;

a sensing element mounted on said support structure for sensing optical radiation and generating an electrical signal in response thereto; and

an encapsulant encapsulating said sensing element on said support structure, said encapsulant including an integral lens for directing incident optical radiation towards said sensing element, said integral lens presenting different fields of view to said sensing element for transverse directions.

28. A vehicle accessory for mounting in a vehicle, said vehicle accessory comprising:

a sensor device comprising;

a support structure;

a sensing element mounted on said support structure for sensing optical radiation and generating an electrical output in response thereto; and

an encapsulant encapsulating said sensing element on said support structure, said encapsulant including an integral anamorphic lens.

45. A sensor device comprising:

a support structure;

a sensing element mounted on said support structure for sensing optical radiation and generating an electrical output in response thereto; and

an encapsulant encapsulating said sensing element on said support structure, said encapsulant including an integral lens for directing incident optical radiation toward said sensing element,

wherein said sensing element has an active sensing area of less than 1 mm².

49. A sensor device comprising:

a support structure;

a sensing element mounted on said support structure for sensing optical radiation and generating an electrical output in response thereto; and

an integral encapsulant configured to encapsulate said sensing element on said support structure, said encapsulant having at least a first zone and a second zone, the second zone exhibiting at least one different characteristic from the first zone.