Optical transmit assembly including thermally isolated laser, temperature sensor, and temperature driver

• US 7,701,988 B2
• Filed: 04/20/2005
• Issued: 04/20/2010
• Est. Priority Date: 04/20/2005
• Status: Active Grant

• Current Assignee: II-VI Delaware, Inc. (Coherent Corp.)
• Original Assignee: Finisar Corporation (II-VI Incorporated)
• Inventors: Hosking, Lucy G.
• Primary Examiner(s): Harvey; Minsun
• Assistant Examiner(s): Nguyen; Tuan N.
• Application Number:
  US11/110,236
• Publication Number:
  US 20060239313A1
• Time in Patent Office: 1,826 Days
• Field of Search: 372/34, 372/36, 428/641, 257/467, 398/14
• US Class Current: 372/34
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01S 5/02325 Mechanically integrated components on mount members or optical micro-benches
• CPC Class Codes: H01S 5/02415 by using a thermo-electric cooler [TEC], e.g. Peltier element
• CPC Class Codes: H01S 5/02446 Cooling being separate from the laser chip cooling
• CPC Class Codes: H01S 5/026 Monolithically integrated components, e.g. waveguides, monitoring photo-detectors, drivers stabilisation of output H01S5/06
• CPC Class Codes: H01S 5/0261 Non-optical elements, e.g. laser driver components, heaters H01S5/0265 takes precedence
• CPC Class Codes: H01S 5/06804 by monitoring an external parameter, e.g. temperature

Abstract

An optical transmit assembly in which a laser and temperature sensor are mounted on a first substrate without other heat generating components. Other heat generating components may be mounted on a second substrate that is separated from the first substrate by a thermally resistance mechanism. Accordingly, heat that is generated by other components is not as easily transferred to the laser and temperature sensor. This allows the temperature of the temperature sensor to more closely track the temperature of the laser, and allows for more efficient cooling of the laser.

Claims

1. An optical transmit assembly comprising:

one or more circuit components that emit heat therefrom;

a first substrate upon which the one or more circuit components that emit heat are structurally mounted;

a second substrate;

a laser and temperature sensor structurally mounted on the substrate, the temperature sensor being structurally coupled between the laser and the substrate;

a temperature driver thermally coupled to the second substrate; and

a thermal resistance mechanism including a thermally insulating material, the thermal resistance mechanism structurally connecting the first substrate to the second substrate and providing thermal resistance between the first substrate upon which the one or more circuit components are structurally mounted and the combination of the second substrate, the laser and the temperature sensor such that heat that is generated by the one or more circuit components that emit heat therefrom is restricted by the thermal resistant mechanism from being transferred to the laser and temperature sensor, which allows the temperature of the temperature sensor to more closely track the temperatures of the laser since the temperature of the laser and temperature sensor is less susceptible to dynamic temperature fluctuations caused by surrounding circuitry and changes in the laser bias and modulation currents.

2. An optical transmit assembly in accordance with claim 1, further comprising a second heat sink to which the second substrate is thermally coupled.

3. An optical transmit assembly in accordance with claim 1, wherein the one or more circuit components comprise a laser driver that is electrically coupled to the laser.

4. An optical transmit assembly in accordance with claim 1, wherein the temperature sensor is mounted to the substrate, and the laser is mounted to the temperature sensor.

5. An optical transmit assembly in accordance with claim 4, wherein the second substrate comprises a first side and an opposing second side, the temperature sensor being mounted to the first side of the substrate and wherein the temperature driver is mounted to the second side of the substrate.

6. An optical transmit assembly in accordance with claim 1, wherein a thermally conductive piece is positioned between the temperature driver and the second substrate.

7. An optical transmit assembly in accordance with claim 1, wherein the temperature driver is thermally coupled with the laser.

8. An optical transmit assembly in accordance with claim 1, further comprising a first heat sink thermally coupled to the temperature driver.

9. An optical transmit assembly comprising:

a first substrate having a top surface and a bottom surface, the bottom surface of the substrate being directly opposed to the top surface of the first substrate;

a laser having a top surface and a bottom surface, the bottom surface of the laser being directly opposed to the top surface of the laser;

a temperature sensor having a top surface and a bottom surface,

the bottom surface of the laser being directly opposed to the top surface of the

temperature sensor, the bottom surface of the temperature sensor being, in direct contact with a top surface of the first substrate and the top surface of the temperature sensor being in direct contact with the bottom surface of the laser such that the temperature sensor is sandwiched between the bottom surface of the laser and the top surface of the first substrate;

a temperature driver thermally coupled to the first substrate;

a second substrate separated from the first substrate by a thermal resistance mechanism; and

one or more circuit components that emit heat therefrom, the one or more circuit components being structurally mounted on the second substrate;

wherein the first and second substrate lie within the same plane in a side-by-side configuration with the thermal resistive connecting in between.

10. An optical transmit assembly in accordance with claim 9, wherein the temperature driver is thermally isolated from the second substrate.

11. An optical transmit assembly in accordance with claim 9, wherein the circuit components are thermally isolated from the laser and temperature sensor.

12. An optical transmit assembly in accordance with claim 9, wherein the first substrate is structurally bonded to the second substrate using a thermally insulating material.

13. An optical transmit assembly in accordance with claim 9, wherein the circuit components comprise a laser driver that is electrically coupled to the laser.