Semiconductor devices and methods for time-of-flight and proximity measurements
AssigneeAms AG
InventorMartin Münzer
Life of this patent
Estimating the term…
Abstract
An emitter of electromagnetic radiation is configured for modes of operation providing fields of illumination of different widths, and a photodetector is configured for time-of-flight and proximity measurements by detecting electromagnetic radiation that is emitted by the emitter and reflected to the photodetector. The emitter is operated by a driver, which is configured for an alternation between the modes of operation. A time-of-flight measurement is performed when the field of illumination is narrow, and a proximity or ambient light measurement is performed when the field of illumination is wide.
Claims8
A semiconductor device, comprising:
- an emitter of electromagnetic radiation, wherein the emitter is configured for modes of operation providing fields of illumination of different widths;
- and
- a photodetector configured for time-of-flight and proximity measurements by detecting the electromagnetic radiation that is emitted by the emitter and reflected to the photodetector;
- wherein the emitter is operated by a driver, which is configured for alternation between the modes of operation,
- wherein the emitter is a vertical-cavity surface-emitting laser,
- wherein the driver is configured to generate driving currents,
- wherein a first driving current of the driving currents is below a lasing threshold of the emitter,
- wherein a second driving current of the driving currents is above the lasing threshold of the emitter,
- wherein the first driving current is provided for a proximity or ambient light measurement, and
- wherein the second driving current is provided for a time-of-flight measurement.
A method for time-of-flight and proximity measurements, the method comprising:
- operating an emitter of electromagnetic radiation alternatively in different modes of operation providing fields of illumination of different widths;
- performing a time-of-flight measurement when a field of illumination of the fields of illumination is narrow, and a proximity or ambient light measurement when the field of illumination of the fields of illumination is wide;
- using a vertical-cavity surface-emitting laser as the emitter;
- and
- using a driver to generate driving currents for the emitter;
- wherein the proximity or ambient light measurement is performed when a first driving current of the driving currents is below a lasing threshold of the emitter, and
- wherein the time-of-flight measurement is performed when a second driving current of the driving currents is above the lasing threshold of the emitter.
Dependencies are inferred from the claim text.