Device and method for generating a laser pulse

Patent metadata

Field	Value
Publication number	US-11329451-B2
Application number	US-201816759048-A
Country	US
Kind code	B2
Filing date	Oct 30, 2018
Priority date	Oct 30, 2017
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

A device for generating a laser pulse. The device includes a laser diode that includes a first diode and a second diode, so that the laser diode includes a first anode, a second anode, and a cathode. The device further includes a first voltage potential that is electrically connected to the second anode, a second voltage potential that has a lower value than the first voltage potential, a first switch that is electrically connected to the first anode and to the second voltage potential, and a second switch that is electrically connected to the cathode and to the second voltage potential. A resistor is electrically connected to the first anode and to the second anode.

First claim

What is claimed is:

1. A device for generating a laser pulse, comprising:
a laser diode that includes a first diode and a second diode, wherein the first diode has a first anode, the second diode has a second anode, and the first and second diodes share a single cathode;
a first voltage potential electrically connected to the second anode;
a second voltage potential that has a lower value than the first voltage potential;
a resistor;
a first switch that is electrically connected to the first anode and to the second voltage potential, wherein:
the first anode is electrically connected between the resistor and first switch;
the resistor is electrically connected between the first anode and the second anode; and
the first switch is configured to switch between:
(a) a closed state in which the first switch connects the first voltage potential to the second voltage potential via the resistor and provides the second voltage potential to the first anode; and
(b) an open state in which the first voltage potential is not connected to the second voltage potential via the first switch and in which the first anode is not connected to the second voltage potential and is connected to the first voltage potential via the resistor; and
a second switch that, when closed, electrically connects the shared single cathode to the second voltage potential.

2. The device as recited in claim 1 , wherein the resistor has a resistance of less than 1 Ω).

3. The device as recited in claim 1 , wherein the first switch and the second switch are NMOS transistors.

4. The device as recited in claim 1 , wherein the laser diode has a monolithic design.

5. The device as recited in claim 1 , wherein the second voltage potential is provided by at least one storage capacitor.

6. A method for generating a laser pulse using a first voltage potential, a second voltage potential, and a laser diode that includes a first diode that has a first anode and a second diode that has a second anode, wherein a single cathode is shared by the first diode and the second diode, and wherein a resistor is electrically connected between the first anode and the second anode, the method comprising the following steps:
closing a first switch that is electrically connected to the first anode and to the second voltage potential, so that a first current path is formed that extends from the first voltage potential to the second voltage potential via the resistor;
closing a second switch that is electrically connected to the shared single cathode and to the second voltage potential, so that (a) the shared single cathode has the second voltage potential, and (b) a pump current is generated that introduces energy within a second current path, the second current path extending from the first voltage potential to the second voltage potential via the second diode;
in response to a first threshold being reached while the first switch and the second switch are closed due to the closing of the first switch and the closing of the second switch, opening the first switch while the second switch remains closed, so that a course of the first current path is changed to extend from the first voltage potential to the second voltage potential via the resistor and the first diode, the opening of the first switch in response to the first threshold being reached and while the second switch remains closed thereby causing the laser pulse to be emitted; and
subsequent to the emission of the laser pulse, opening the second switch, thereby causing a voltage drop across the first and second diodes.

7. The method as recited in claim 6 , wherein the first threshold value represents a first time period.

8. The method as recited in claim 6 , wherein the first threshold value is a temperature value, so that the first threshold is reached when a temperature of a substrate of the laser diode rises to the temperature value.

9. The method as recited in claim 6 , wherein the first threshold value represents a value of the pump current.

10. The method as recited in claim 6 , wherein the closing of the first switch occurs while the second switch is open, and the closing of the second switch is performed after the closing of the first switch.

11. The method as recited in claim 10 , wherein the closing of the first switch causes a voltage drop across the first diode without a voltage drop across the second diode.

12. The method as recited in claim 11 , wherein the closing of the second switch causes a voltage rise across the first diode and across the second diode.

13. The method as recited in claim 12 , wherein the opening of the first switch causes a further voltage rise across the first diode without causing a rise of voltage across the second diode.

14. A vehicle that includes a device for generating a laser pulse, the device comprising:
a laser diode that includes a first diode and a second diode, wherein the first diode has a first anode, the second diode has a second anode, and the first and second diodes share a single cathode;
a first voltage potential electrically connected to the second anode;
a second voltage potential that has a lower value than the first voltage potential;
a resistor;
a first switch that is electrically connected to the first anode and to the second voltage potential, wherein:
the first anode is electrically connected between the resistor and first switch;
the resistor is electrically connected between the first anode and the second anode; and
the first switch is configured to switch between:
(a) a closed state in which the first switch connects the first voltage potential to the second voltage potential via the resistor and provides the second voltage potential to the first anode; and
(b) an open state in which the first voltage potential is not connected to the second voltage potential via the first switch and in which the first anode is not connected to the second voltage potential and is connected to the first voltage potential via the resistor; and
a second switch that, when closed, electrically connects the shared single cathode to the second voltage potential.

Assignees

• Bosch Gmbh Robert

Inventors

• Pannwitz Axel

Classifications

• H01S5/0615

  Q-switching, i.e. in which the quality factor of the optical resonator is rapidly changed · CPC title

• H01S5/06253

  Pulse modulation · CPC title

• G01S7/484

  Transmitters · CPC title

• H01S5/0428 Primary

  for applying pulses to the laser · CPC title

• H01S5/02326

  Arrangements for relative positioning of laser diodes and optical components, e.g. grooves in the mount to fix optical fibres or lenses · CPC title