Systems for emitting uncooled light
AssigneeAlmae Technologies
InventorHélène Debregeas
Life of this patent
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Abstract
An uncooled light-emitting system includes a light-emitting device. The light-emitting device includes at least one first set of layers of semiconductor materials configured to form at least one first active zone able to emit light and a heater. The first active zone is optimized to function at a nominal temperature. The heater extends at least along the first active zone and is situated at a predetermined maximum distance from the first active zone less than or equal to 100 micrometers. The heater is configured, in operation, to produce a heating of the first active zone. A control unit is configured to start up the heater only if the temperature of the device is determined to be strictly lower than a predetermined set point temperature less than or equal to the nominal temperature.
Claims17
An uncooled light-emitting system (100) comprising:
- a light-emitting device (400) comprising:
- at least one first set of layers of semiconductor materials (403) configured to form at least one first active zone (401) able to emit light, said first active zone (401) being optimized to function at a nominal temperature;
- and
- a heater (460) extending at least along said first active zone (401) and situated at a predetermined maximum distance from said first active zone (401) less than or equal to about 100 micrometers, said heater being configured, in operation, to produce a heating of said first active zone (401);
- means (500) for determining the temperature of the device;
- and
- a control unit (600) configured to start up said heater (460) only if said temperature of the device is strictly lower than predetermined set point temperature less than or equal to said nominal temperature, the heating produced by the heater enabling a rise in the temperature of the device to about the value of the set point temperature.
The system as claimed in any one of the preceding claims, in which said maximum distance between the active zone (401) and the heater (460) is a distance between about 5 micrometers and about 100 micrometers.
The system as claimed in any one of the preceding claims, in which said maximum distance between the active zone (401) and the heater (460) is a distance between about 5 micrometers and about 20 micrometers.
The system as claimed in any one of the preceding claims, in which the means (500) for determining the temperature of the device comprise a device for measuring the wavelength of the light emitted by the light-emitting device.
The system as claimed in any one of the preceding claims, in which said set point temperature is strictly lower than said nominal temperature.
The system as claimed in any one of the preceding claims, in which the heater (460) comprises a metal strip disposed on an external layer of said first set of layers of semiconductor materials (403).
The system as claimed in any one of the preceding claims, in which said heater (460) comprises at least one ground (421) electrically connected to a ground of said set of layers of semiconductor materials (403) and at least one electrical contact (422) electrically insulated from said ground (421).
The system as claimed in any one of the preceding claims, in which said first active zone (401) forms a distributed Bragg grating laser.
The system as claimed in any one of the preceding claims, in which:
- said first set of layers of semiconductor materials (403) is further configured to form a second active zone (484) able to receive and to modulate light emitted by said first active zone (401), said second active zone being optimized to function at said nominal temperature;
- and
- said heater (460) further extends along said second active zone (484) and is disposed at said maximum distance from said second active zone (484), said heater further being configured to produce a heating of said second active zone (484).
A method of controlling the temperature in an uncooled light-emitting system as claimed in any one of the preceding claims, said method comprising:
- choosing a set point temperature lower than or equal to said nominal temperature of the device;
- determining the temperature of the device;
- and
- the control unit (600) starting up the heater only if said temperature of the device is strictly lower than said set point temperature, the heating produced by the heater enabling a rise in the temperature of the device to about the value of said set point temperature.
Dependencies are inferred from the claim text.