Light receiver having a plurality of avalanche photodiode elements and method for supplying a bias voltage

Patent metadata

Field	Value
Publication number	US-10584998-B2
Application number	US-201715850385-A
Country	US
Kind code	B2
Filing date	Dec 21, 2017
Priority date	Dec 22, 2016
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

A light receiver ( 22 ) having a plurality of avalanche photodiode elements ( 24 ) each configured to be biased with a bias voltage above a breakdown voltage and thus to be operated in a Geiger mode for triggering a Geiger current upon light reception, the light receiver ( 22 ) comprising a plurality of bias voltage terminals ( 40 a - c ) providing different bias voltages, wherein the avalanche photodiode elements ( 24 ) form a plurality of groups ( 42 1 - 42 n ), and wherein the avalanche photodiode elements ( 24 ) of a group ( 42 1 - 42 n ) are each supplied with a same one of the different bias voltages.

First claim

The invention claimed is:

1. A light receiver ( 22 ) having a plurality of avalanche photodiode elements ( 24 ) each configured to be biased with a bias voltage above a breakdown voltage and thus to be operated in a Geiger mode for triggering a Geiger current upon light reception, the light receiver ( 22 ) comprising:
a plurality of bias voltage terminals ( 40 a - c ) providing different bias voltages, and having a different positive potential and a plurality of bias voltage terminals ( 40 a 2 - c 2 ) having a different negative potential in order to supply avalanche photodiode elements ( 24 ) with different bias voltages by connections to a positive potential and a negative potential from both sides,
wherein the avalanche photodiode elements ( 24 ) form a plurality of groups ( 421 - 42 n ), and wherein the avalanche photodiode elements ( 24 ) of a group ( 421 - 42 n ) are each supplied with a same one of the different bias voltages.

2. The light receiver ( 22 ) according to claim 1 ,
wherein the avalanche photodiode elements ( 24 ) of a group ( 421 - 42 n ) are selectively supplied with one of the different bias voltages.

3. The light receiver ( 22 ) according to claim 1 ,
wherein a switching element ( 441 - 44 m ) is arranged between the avalanche photodiode elements ( 24 ) of at least one group ( 421 - 42 n ) and the bias voltage terminals ( 40 a - c ).

4. The light receiver ( 22 ) according to claim 1 ,
wherein at least two of the plurality of bias voltage terminals ( 40 a - c ) have an external connection ( 48 ).

5. The light receiver ( 22 ) according to claim 1 ,
wherein at least one of the bias voltage terminals ( 40 a - c ) is internal, and wherein at least one voltage adjusting element ( 50 a - c ) for generating different bias voltages from one external voltage ( 48 ) is provided.

6. The light receiver ( 22 ) according to claim 5 ,
wherein the voltage adjusting element ( 50 a - c ) is configured for voltage subtraction.

7. The light receiver ( 22 ) according to claim 5 ,
wherein the voltage adjusting element ( 50 a - c ) comprises a control ( 52 a - c ) for setting the bias voltage to be generated.

8. The light receiver ( 22 ) according to claim 1 ,
wherein the avalanche photodiode elements ( 24 ) of at least one group ( 421 - 42 n ) are fixedly connected to a respective bias voltage terminal ( 40 a - c ).

9. The light receiver ( 22 ) according to claim 1 ,
wherein the groups ( 421 - 42 n ) form a checkerboard pattern, a concentric pattern, or several laterally displaced regions.

10. The light receiver ( 22 ) according to claim 1 ,
wherein at least one bias voltage terminal ( 40 a - c ) provides a bias voltage above the breakdown voltage and at least one bias voltage terminal ( 40 a - c ) provides a bias voltage below the breakdown voltage.

11. The light receiver ( 22 ) according to claim 1 ,
wherein bias voltage terminals ( 40 a - c ) provide different bias voltages above the breakdown voltage.

12. The light receiver ( 22 ) according to claim 1 ,
wherein the groups ( 4211 - 42 nm ) form a matrix arrangement, and wherein the bias voltage terminals ( 40 a - c ) having a positive potential are connected to a line ( 42 i 1 - 42 im ) or a column ( 421 j - 42 nj ), and accordingly the bias voltage terminals ( 40 a 2 - c 2 ) having a negative potential are connected to a column ( 421 j - 42 nj ) or a line ( 42 i 1 - 42 im ).

13. The light receiver ( 22 ) according to claim 1 , further comprising:
at least one temperature sensing element ( 54 ) for detecting an operating temperature of the avalanche photodiode elements ( 24 ); and
a temperature compensation unit ( 56 ) for adjusting the bias voltages in dependence on the detected operating temperature.

14. The light receiver ( 22 ) according to claim 13 ,
wherein all bias voltages are adjusted at a same time on a common path.

15. The light receiver ( 22 ) according to claim 1 , further comprising:
an active current limiting unit ( 56 ) configured to reduce the bias voltages upon a current flowing in the light receiver ( 22 ) exceeding a current threshold.

16. The light receiver ( 22 ) according to claim 15 ,
wherein all bias voltages are reduced at a same time on a common path.

17. An optoelectronic sensor ( 10 ) comprising at least one light receiver ( 22 ), comprising:
the light receiver ( 22 ) having a plurality of avalanche photodiode elements ( 24 ) each configured to be biased with a bias voltage above a breakdown voltage and thus to be operated in a Geiger mode for triggering a Geiger current upon light reception,
the light receiver ( 22 ) comprising a plurality of bias voltage terminals ( 40 a - c ) providing different bias voltages, and having a different positive potential and a having a different negative connections to a positive potential and a negative potential from both sides,
wherein the avalanche photodiode elements ( 24 ) form a plurality of groups ( 421 - 42 n ), and wherein the avalanche photodiode elements ( 24 ) of a group ( 421 - 42 n ) are each supplied with a same one of the different bias voltages.

18. The optoelectronic sensor ( 10 ) according to claim 17 , further comprising:
the sensor ( 10 ) being configured as a sensor ( 10 ) for measuring distances according to a time of flight method.

19. The optoelectronic sensor ( 10 ) according to claim 17 , further comprising:
the sensor ( 10 ) being configured as a code reader.

20. The optoelectronic sensor ( 10 ) according to claim 17 , further comprising:
the sensor ( 10 ) being configured for data transmission.

21. A method for supplying a plurality of avalanche photodiode elements ( 24 ) of a light receiver ( 22 ) with a bias voltage,
wherein at least some of the avalanche photodiode elements ( 24 ) are each biased with a bias voltage above a breakdown voltage and are thus operated in a Geiger mode,
wherein the avalanche photodiode elements ( 24 ) form a plurality of groups ( 421 - 42 n ),
and wherein avalanche photodiode elements ( 24 ) of one group ( 421 - 42 n ) are supplied with a different bias voltage than avalanche photodiode elements ( 24 ) of another group ( 421 - 42 n ), and a plurality of bias voltage terminals ( 40 a - c ), having a different positive potential different bias voltages by connections to a positive potential and a negative potential from both sides.

Assignees

• Sick Ag

Inventors

• Clemens Klaus
• Hug Gottfried
• Seitz Stefan
• Tschuch Sebastian

Classifications

• G01J2001/448

  Array [CCD] · CPC title

• G01J2001/4406

  Plural ranges in circuit, e.g. switchable ranges; Adjusting sensitivity selecting gain values · CPC title

• G01J1/46

  using a capacitor · CPC title

• G01S7/4863 Primary

  Detector arrays, e.g. charge-transfer gates · CPC title

• G01S7/4816

  of receivers alone · CPC title