Sensor and use of a sensor in a 3-D position detection system

Patent metadata

Field	Value
Publication number	US-11567565-B2
Application number	US-201816647193-A
Country	US
Kind code	B2
Filing date	Sep 21, 2018
Priority date	Sep 22, 2017
Publication date	Jan 31, 2023
Grant date	Jan 31, 2023

Abstract

A sensor and a 3-D position detection system are disclosed. In an embodiment a sensor includes at least one sensor chip configured to detect radiation, at least one carrier on which the sensor chip is mounted and a cast body that is transmissive for the radiation and that completely covers the sensor chip, wherein a centroid shift of the sensor chip amounts to at most 0.04 mrad at an angle of incidence of up to at least 60°, wherein the cast body comprises a light inlet side that faces away from the sensor chip, and the light inlet side comprises side walls bounding it on all sides, wherein the side walls are smooth, planar and transmissive for the radiation, wherein a free field-of-view on the light inlet side has an aperture angle of at least 140°, and wherein the cast body protrudes in a direction away from the sensor chip beyond a bond wire.

First claim

The invention claimed is:

1. A sensor comprising:
at least one sensor chip configured to detect radiation;
at least one carrier on which the sensor chip is mounted; and
a cast body that is transmissive for the radiation and that completely covers the sensor chip,
wherein a centroid shift of the sensor chip amounts to at most 0.04 mrad at an angle of incidence of up to at least 60°,
wherein the cast body comprises a light inlet side that faces away from the sensor chip, and the light inlet side comprises side walls bounding it on all sides,
wherein the side walls are smooth, planar and transmissive for the radiation,
wherein a free field-of-view on the light inlet side has an aperture angle of at least 140°,
wherein the sensor chip is contacted electrically with at least one bond wire, and
wherein the cast body protrudes in a direction away from the sensor chip beyond the bond wire by at most 120 μm so that a thickness of the cast body at the side that faces away from the sensor chip lies at a maximum of 0.2 mm and so that the thickness is smaller than a thickness of the sensor chip.

2. The sensor according to claim 1 , wherein the cast body extends beyond the sensor chip equally all around when seen from above, and wherein a ratio of a diagonal length of the cast body and of the sensor chip lies between 1.1 and 1.4 inclusive.

3. The sensor according to claim 1 , wherein the light inlet side is smooth and planar, and wherein an angle between the side walls and the light inlet side, seen in cross-section, is between 94° and 106° inclusive.

4. The sensor according to claim 1 , wherein the sensor chip is contacted electrically at an upper chip side that faces away from the carrier with the bond wire, and wherein the bond wire is located entirely in the cast body.

5. The sensor according to claim 1 , wherein the sensor chip comprises a plurality of electrical contact points at the side that faces away from the carrier, and wherein the electrical contact points are arranged symmetrically around the side of the sensor chip.

6. The sensor according to claim 1 , wherein the carrier and the cast body are flush against one another at the sides, and wherein chip side walls of the sensor chip are not transmissive for the radiation and/or do not supply any contribution to a detector signal.

7. The sensor according to claim 1 , wherein the centroid shift of the sensor chip amounts to at most 0.15 mrad at angles of incidence of up to at least 40°, wherein the centroid shift depends on the angle of incidence and up to angles of incidence of at least 60° are approximatable by a quadratic function with an error of at most 0.003 mrad, and wherein the centroid shift at small angles of incidence has a different arithmetic sign than at large angles of incidence, and a boundary between small and large angles of incidence lies between 7° and 25° inclusive.

8. The sensor according to claim 1 , wherein the side of the cast body that faces away from the sensor chip is roughened so that the sensor chip is configured to receive a Lambertian propagation of the radiation as a result of the roughening, and wherein the cast body is made of a material that is clear for the radiation.

9. The sensor according to claim 1 , wherein the carrier is designed to reflect diffusely in regions next to the sensor chip up to a surface proportion of at least 90%.

10. A 3D position detection system comprising:
at least one radiation source configured to generate the radiation; and
a user device comprising a plurality of sensors, wherein at least one sensor of the plurality of sensors is the sensor according to claim 1 ,
wherein the sensors are configured to determine angles between the user device and the radiation source so that a spatial position and an alignment of the user device is ascertainable based on the angles.

11. The 3D position detection system according to claim 10 , wherein each sensor chip is contacted electrically at an upper chip side that faces away from the respective carrier with bond wires, and wherein bond wires are located entirely in the cast body.

12. The 3D position detection system according to claim 10 , wherein each sensor chip comprises a plurality of electrical contact points at the sides that face away from the respective carrier, and wherein the electrical contact points are arranged symmetrically around the sides of the sensor chips.

13. The 3D position detection system according to claim 10 , wherein the respective carrier and the associated cast body are flush against one another at the sides, and wherein chip side walls of the respective sensor chip are not transmissive for the radiation and/or do not supply any contribution to a detector signal.

14. The 3D position detection system according to claim 10 , wherein the centroid shift of the sensor chip amounts to at most 0.15 mrad at angles of incidence of up to at least 40°, wherein the centroid shift depends on the angle of incidence and up to angles of incidence of at least 60° are approximatable by a quadratic function with an error of at most 0.003 mrad, and wherein the centroid shift at small angles of incidence has a different arithmetic sign than at large angles of incidence, and a boundary between small and large angles of incidence lies between 7° and 25° inclusive.

15. The 3D position detection system according to claim 10 , wherein the sides of the cast bodies that face away from the sensor chips is roughened so that the sensor chips are configured to receive a Lambertian propagation of the radiation as a result of the roughening, and wherein the cast bodies are made of a material that is clear for the radiation.

16. The 3D position detection system according to claim 10 , wherein the carriers are designed to reflect diffusely in regions next to the sensor chips up to a surface proportion of at least 90%.

17. The 3D position detection system according to claim 10 , wherein the user device is a pair of glasses for virtual reality with at least one display, and wherein the display is configured to display three-dimensional images.

18. A method for using the 3D position detection system according to claim 10 , wherein the 3D position detection system comprises at least five of the sensor chips, the method comprising:
providing pulsed, laminar and near infra-red laser radiation;
moving the radiation over a spatial region in which the user device is located so that multiple sequentially following pulses of the laser radiation impinge on a relevant sensor chip;
detecting a temporal curve of intensity of impinging pulses by the relevant sensor chip; and
ascertaining an angle to an associated radiation source based on detecting the temporal curve of intensity.

Assignees

• Osram Oled Gmbh

Inventors

• Dietze Daniel
• Assig Maximilian
• Jaeger Claus

Classifications

• G06T19/00

  Manipulating three-dimensional [3D] models or images for computer graphics · CPC title

• G01S3/789

  using rotating or oscillating beam systems, e.g. using mirrors, prisms · CPC title

• G06F3/012 Primary

  Head tracking input arrangements · CPC title

• G01S1/703

  Details · CPC title

• H10F77/50

  Encapsulations or containers (for photovoltaic modules H10F19/80) · CPC title