Window mounting for optical sensor

• US 20040211892A1
• Filed: 04/23/2003
• Published: 10/28/2004
• Est. Priority Date: 04/23/2003
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Wellman, William H., Stallard, Charles R.
• Granted Patent: US 7,002,139 B2
• Time in Patent Office: Days
• US Class Current: 250/239
• CPC Class Codes: G02B 7/028 with means for compensating for changes in temperature or for controlling the temperature; thermal stabilisation
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 31/0203 Containers; Encapsulations , e.g. encapsulation of photodiodesfor photovoltaic devices H01L31/048; for organic photosensitive devices H10K30/80
• CPC Class Codes: H01L 31/02325 the optical elements not being integrated nor being directly associated with the device

Abstract

A window mounting system for optical sensors including a removable connection for window replacement, an alignment system to assure precision registration of the window or dome with the sensor internal optics, and thermal insulation to limit heat transfer from the window to the optics housing and sensor. The removable connection maintains precise optical alignment of curved domes with significant optical power, yet also is effective with simple flat windows.

Claims

1. An optical sensor cover system comprising:

an optics housing adapted to house an optical sensor therein; and

a window connected to the optics housing by a removable connection,

wherein the removable connection comprises thermal insulation between the window and the optics housing which comprises a heat transfer limiting system to limit heat transfer from the window to the optics housing.

2. An optical sensor cover system as in claim 1 wherein the removable connection comprises an O-ring seal pressing against the window.

3. An optical sensor cover system as in claim 2 further comprising a main housing having the optics housing connected thereto, wherein the removable connection comprises a flange member removably connected to the main housing which pressing the O-ring seal against the window and, wherein the O-ring seal forms a seal with the main housing and the window.

4. An optical sensor cover system as in claim 1 wherein the window comprises a general dome shape, and wherein the heat transfer limiting system comprises the dome window contacting the optics housing only along an interior surface of the optics housing that also aligns the dome window relative to the optics housing and limits conductive heat transfer from the dome window to the optics housing.

5. An optical sensor cover system as in claim 1 further comprising a heater assembly connected between the optics housing and the window, wherein the heater assembly is thermally insulated from the optics housing.

6. An optical sensor cover system as in claim 1 further comprising a window frame, wherein the window is bonded to the window frame, and wherein the window frame is removably connected to the optics housing.

7. An optical sensor cover system as in claim 6 further comprising alignment members extending between the window frame and the optics housing for aligning the window relative to an open area of the optics housing.

8. An optical sensor cover system as in claim 6 wherein the transfer limiting system comprises thermal insulation between the window and the optics housing.

9. An optical sensor cover system as in claim 8 wherein the thermal insulation is located in the window frame.

10. An optical sensor cover system comprising:

an optics housing adapted to house an optical sensor therein; and

a dome shaped window connected to the optics housing by a removable connection,

wherein the dome window contacts the optics housing only along a concave interior surface at a protruding surface of the optics housing to align the dome window relative to the optics housing and limit conductive heat transfer from the dome window to the optics housing.

11. An optical sensor cover system as in claim 10 wherein the removable connection comprises an O-ring seal pressing against the window.

12. An optical sensor cover system as in claim 11 further comprising a main housing having the optics housing connected thereto, wherein the removable connection comprises a flange member removably connected to the main housing which pressing the O-ring seal against the window and, wherein the O-ring seal forms a seal with the main housing and the window.

13. An optical sensor cover system as in claim 10 further comprising a heater assembly connected between the optics housing and the dome window, wherein the heater assembly is thermally insulated from the optics housing.

14. A method of mounting a dome window to an optics housing comprising steps of:

positioning the dome window on the optics housing with only a portion of an interior concave surface of the dome window contacting the optics housing at an outer tip of the optics housing; and

applying force to the dome window by an O-ring seal to align the dome window at a predetermined position on the optics housing,

wherein an area of contact between the outer tip of the optics housing and the dome window is small to limit conductive heat transfer from the dome window to the optics housing, and wherein the seal can be removed to remove the dome window from the optics housing.

15. A method as in claim 14 wherein to the optics housing is located in a main housing, and wherein a mounting flange is removably connected to the main housing, the mounting flange applying force to the O-ring seal for the O-ring seal to apply force to the dome window.

16. A method as in claim 15 wherein the O-ring seal forms a seal with the dome window and the main housing at an open junction between the dome window and the main housing.

17. A method as in claim 14 further comprising positioning a heating assembly against the dome window, and thermally insulating the heating assembly from the optics housing.

18. A method of mounting a window to an optics housing, the method comprising steps of:

bonding the window to a window frame;

removably connecting the window frame to the optics housing at a removable connection, the removable connection comprising alignment members extending between the window frame and the optics housing to align the window relative to an open area of the optics housing; and

providing heat transfer insulation between the window and the optics housing.

19. A method as in claim 18 further comprising connecting a heater to the window, and thermally insulating the heater from the optics housing.

20. A method as in claim 19 wherein the heater is located at least partially in the window frame.