Light receiver having geiger-mode avalanche photodiodes and method for reading out

Patent metadata

Field	Value
Publication number	US-10436638-B2
Application number	US-201715617398-A
Country	US
Kind code	B2
Filing date	Jun 8, 2017
Priority date	Jun 17, 2016
Publication date	Oct 8, 2019
Grant date	Oct 8, 2019

Abstract

A light receiver (50) is provided having a plurality of avalanche photodiode elements (10) that are each biased by a bias above a breakdown voltage and that are thus operated in a Geiger mode to trigger a Geiger current on light reception. The avalanche photodiode elements (10) have a first connector (20, 22, 28a-b) and a second connector (20, 22, 28a-b). A first signal tapping circuit (12) for reading out the avalanche photodiode elements is connected to one of the connectors (20, 22, 28a-b). In this respect, a second signal tapping circuit (12) for reading out the avalanche photodiode elements (10) is connected to the other connector (20, 22, 28a-b).

First claim

The invention claimed is:

1. A light receiver having a plurality of avalanche photodiode elements that are each biased by a bias above a breakdown voltage and that are thus operated in a Geiger mode to trigger a Geiger current on light reception, wherein the avalanche photodiode elements have a first connector and a second connector; wherein a first signal tapping circuit for reading out the avalanche photodiode elements is connected to one of the first and second connectors, and wherein a second signal tapping circuit for reading out the avalanche photodiode elements is connected to the other one of the first and second connectors
wherein at least one of the first signal tapping circuit and the second signal tapping circuit has an active coupling element, the active coupling element having an input that is connected to one of the first and second connectors and having an output; wherein the coupling element maps a Geiger current of the respective avalanche photodiode element at the input to a measured current corresponding in progression and level to the Geiger current in that the input for the Geiger current forms a virtual short circuit against a potential and the output is decoupled from the input.

2. The light receiver in accordance with claim 1 ,
wherein the first connector is arranged on the anode side and the second connector is arranged on the cathode side of the respective avalanche photodiode element.

3. The light receiver in accordance with claim 1 ,
wherein the avalanche photodiode elements are biased via the first connector and via the second connector.

4. The light receiver in accordance with claim 3 ,
wherein a charge unit is respectively arranged between the avalanche photodiode element and the first connector or the second connector and the charge unit is bridged by a capacitor connected in parallel.

5. The light receiver in accordance with claim 1 ,
wherein the avalanche photodiode elements have a third connector; with the first connector being configured for a capacitive decoupling of the Geiger current; and with the avalanche photodiode elements being biased via the second connector and the third connector.

6. The light receiver in accordance with claim 1 ,
wherein the avalanche photodiode elements have a third connector and a fourth connector and a first charge unit is respectively arranged between the avalanche photodiode element and the third connector and a second charge unit is arranged between the avalanche photodiode element and the fourth connector; and wherein the avalanche photodiode elements are biased via the third connector and via the fourth connector.

7. The light receiver in accordance with claim 6 ,
wherein the first charge unit is bridged to the first connector by a first capacitor connected in parallel and the second charge unit is bridged to the second connector by a second capacitor connected in parallel.

8. The light receiver in accordance with claim 1 ,
wherein the avalanche photodiode elements form a matrix arrangement; wherein a plurality of first signal tapping circuits are each connected to the first connectors of the avalanche photodiode elements of a column and a plurality of second signal tapping circuits are each connected to the second connectors of the avalanche photodiode elements of a row.

9. The light receiver in accordance with claim 1 ,
wherein the avalanche photodiode elements form a linear arrangement divisible into groups; wherein a plurality of first signal tapping circuits are each connected to the first connectors of the avalanche photodiode elements of a group and a plurality of second signal tapping circuits are each connected to the second connectors of an avalanche photodiode element from each group.

10. The light receiver in accordance with claim 1 ,
wherein avalanche photodiode elements are connected in parallel and generate a common signal.

11. An optoelectronic sensor having at least one light receiver constructed according to claim 1 ,
wherein the sensor is configured for distance measurement in accordance with a time of flight process and/or is configured for data transmission.

12. A method for reading out the avalanche photodiode elements in the light receiver of claim 1 , the method comprising:
reading the avalanche photodiodes by the first signal tapping circuit; and
reading the avalanche photodiode elements by the second signal tapping circuit.

13. The method in accordance with claim 12 ,
wherein an input of an active coupling element for the Geiger current in the first signal tapping circuit and/or in the second signal tapping circuit and connected to one of the first and seconds connectors is virtually short circuited against a potential such that the Geiger current flows into the coupling element practically without change and is mapped there onto a measurement current corresponding to the Geiger current in progression and level at an output of the coupling element, wherein the output is decoupled from the input.

14. The method in accordance with claim 12 ,
wherein the avalanche photodiode elements form a matrix arrangement and each avalanche photodiode element is read out, on the one hand, via a first signal tapping circuit associated with its column and, on the other hand, is read out via a second signal tapping circuit associated with its row.

15. A light receiver having a plurality of avalanche photodiode elements that are each biased by a bias above a breakdown voltage and that are thus operated in a Geiger mode to trigger a Geiger current on light reception, wherein the avalanche photodiode elements have a first connector and a second connector; wherein a first signal tapping circuit for reading out the avalanche photodiode elements is connected to one of the first and second connectors, and wherein a second signal tapping circuit for reading out the avalanche photodiode elements is connected to the other one of the first and second connectors, wherein the avalanche photodiode elements have a third connector; with the first connector being configured for a capacitive decoupling of the Geiger current; and with the avalanche photodiode elements being biased via the second connector and the third connector.

16. A light receiver having a plurality of avalanche photodiode elements that are each biased by a bias above a breakdown voltage and that are thus operated in a Geiger mode to trigger a Geiger current on light reception, wherein the avalanche photodiode elements have a first connector and a second connector; wherein a first signal tapping circuit for reading out the avalanche photodiode elements is connected to one of the first and second connectors, and wherein a second signal tapping circuit for reading out the avalanche photodiode elements is connected to the other one of the first and second connectors, wherein the avalanche photodiode elements have a third connector and a fourth connector and a first charge unit is respectively arranged between the avalanche photodiode element and the third connector and a second charge unit is arranged between the avalanche photodiode element and the fourth connector; and wherein the avalanche photodiode elements are biased via the third connector and via the fourth connector.

17. The light receiver in accordance with claim 16 ,
wherein the first charge unit is bridged to the first connector by a first capacitor connected in parallel and the second charge unit is bridged to the second connector by a second capacitor connected in parallel.

Assignees

• Sick Ag

Inventors

• Clemens Klaus
• Hug Gottfried
• Seitz Stefan

Classifications

• G01J2001/448

  Array [CCD] · CPC title

• G01J2001/442

  Single-photon detection or photon counting · CPC title

• G01J1/44

  Electric circuits {(for command of an exposure part G03B7/02)} · CPC title

• G01J2001/4466

  Avalanche · CPC title

• G01J1/46 Primary

  using a capacitor · CPC title