1. A method of calibrating an infrared detector using a temperature-adjustable reference surface within its field of view, the method being characterized by the steps of:
a) controlling the temperature of the reference surface to a first surface temperature and measuring the output of the detector over a first stare time, the first temperature and stare time being selected so as to achieve a predetermined first well-fill (Wactual) of the detector pixels at the lowest possible temperature of the reference surface;
b) processing the output measurements of the detector to obtain a first calibration coefficient (coeffcal1);
c) adjusting the temperature of the reference surface to a second surface temperature and measuring the output of the detector over a second stare time period (Sactual), the second temperature and stare time (Sactual) being selected so as to achieve a second predetermined well-fill of the detector pixels
d) processing the output measurements of the detector to obtain a second calibration coefficient (coeffcal2);
e) re-adjusting the temperature of the reference surface to a third surface temperature and measuring the output of the detector over the first stare time period, the third temperature being selected so as to achieve the second predetermined well-fill of the detector pixels over the first stare time period;
f) processing the output measurements of the detector to obtain a third calibration coefficient (coeffcal3); and
g) adjusting the first calibration coefficient (coeffcal1) on the basis of the second and third calibration coefficients (coeffcal2, coeffcal3) obtained.
2. A method according to claim 1, wherein the first predetermined well-fill of the pixels is approximately 50%.
3. A method according to claim 1, wherein the second predetermined well-fill of the pixels is approximately 100%.
4. A method according to claim 1, wherein step g) comprises determining a final calibration coefficient in accordance with the sum of the first (coeffcal1,) and third (coeffcal3) calibration coefficients less the second (coeffcal2,) calibration coefficient.
5. Apparatus for calibrating an infrared detector, the apparatus comprising:
a temperature-controlled reference surface, the detector being located within the apparatus to view the reference surface;
control means for controlling the temperature of the reference surface and the stare time of the detector; and
processing means for receiving output signals from the detector at first, second and third predetermined detector stare time and reference surface temperature combinations and for producing calibration coefficients corresponding to each of the first, second and third predetermined detector stare time and reference surface temperature combination, and for determining final calibration coefficients for the detector from the calibration coefficients determined for each stare time and reference surface temperature combination, characterized in that
in the first stare time and reference surface temperature combination, the first temperature and stare time are selected so as to achieve a predetermined first well-fill (Wactual) of the detector pixels at the lowest possible temperature of the reference surface;
in the second stare time and reference surface temperature combination, the second temperature and stare time (Sactual) are selected so as to achieve a second predetermined well-fill of the detector pixels; and
in the third stare time and reference surface temperature combination, the third temperature is selected so as to achieve the second
predetermined well-fill of the detector pixels over the first stare time period.
6. Apparatus according to claim 5, wherein the first predetermined well-fill of the pixels is approximately 50%.
7. Apparatus method according to claim 5, wherein the second predetermined well-fill of the pixels is approximately 100%.
8. Apparatus according to claim 5, wherein the final calibration coefficient is determined in accordance with the sum of the first (coeffcal1,) and third (coeffcal3) calibration coefficients less the second (coeffcal2,) calibration coefficient.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A connector for connecting power or control systems infrastructure, said connector comprising a male component and a female component, the male and female components comprising cooperating mating surfaces and means for locking the male and female components together, the locking means being retractably mounted within one of the male or female components but extendible from that component into the other of the male or female components to lock the two components together against axial and rotational movement whilst providing a snag free release when the locking means is in the retracted position.
2. A connector according to claim 1, wherein one of the male component or female components has a convex mating surface and the other has a concave mating surface.
3. A connector according to claim 1, wherein the mating surfaces of the male and female components of the connector are partly spherical.
4. A connector according to claim 1 wherein the mating surface of the male and female components are substantially flat.
5. A connector according to claim 1 wherein the locking means comprises a lever pivotally mounted to or within the connector.
6. A connector according to claim 5, wherein the lever is mounted within the female component of the connector.
7. A connector according to claim 1 wherein apertures are formed in the mating surface of the female connector.
8. A connector according to claim 7, wherein the mating surface of the mail and female components are substantially flat, wherein the lever is adapted for movement between a locked condition in which the lever extends through the aperture in the mating surface of the female connector and an unlocked condition in which the lever is retracted from the aperture.
9. A connector according to claim 1, wherein a groove is formed in the outer surface of the male member.
10. A connector according to claim 9, wherein the groove is formed in the mating surface of the male member.
11. A connector according to claim 10, wherein when the male and female components are connected, the lever is adapted to extend, by a biased force, through the aperture in the female member and into the groove of the male member.
12. A connector according to claim 10, wherein a recess is provided in the groove, the end of the lever being received in the recess to lock the male and female members together against radial movement.
13. A connector according to claim 5, wherein means are provided for applying a biasing force to the lever.
14. A connector according to claim 13, wherein the means for applying the biasing force may act on the lever in one direction in a first condition and in another, preferably opposite direction in a second condition.
15. A connector according to claim 10, wherein the depth of the groove increases within the recess.
16. A connector according to claim 1, wherein the connector further comprises actuation means.
17. A connector according to claim 16, wherein the actuation means comprises a housing which is mounted within the body of the female component.
18. A connector according to claim 17, wherein the housing is adapted to be raised and lowered within the body of the female component.
19. A connector according to claim 18, wherein a first portion of the housing extends through the body of the female component.
20. A connector according to claim 16, wherein the actuation means are adapted to control movement of the housing within the body of the female component.
21. A connector according to claim 16, wherein the actuation means comprises a cylinder having a piston moveable within the cylinder.
22. A connector according claim 16, wherein the connector further comprises biasing means for retaining the actuation means in a first condition and locking means for retaining the actuation means in a second condition.
23. A connector according to claim 22, wherein the biasing means comprises a spring.
24. A connector according to claim 22 wherein the locking means comprises a locking member adapted to be moved by the actuation means between a locking position and a release position.
25. A connector according to claim 24, wherein the actuation means further comprises a stop member adapted to co-operate with the locking means for retaining the actuation means in the second condition.
26. A connector according to claim 25, wherein the actuation means comprises a release member for moving the locking member out of co-operating engagement with the stop member to return the actuating means to the first condition.
27. (canceled)
28. A connector for connecting electrical power andor control systems to subsea or surface infrastructure said connector comprising a male component and a female component, the male and female components comprising cooperating mating surfaces, means for latching the male component to the female component to establish a physical connection between the components and further means to establish an electrical connection between the components, the arrangement being such that in use, the physical connection is made before the electrical connection when the male and female components are assembled and the electrical connection is broken before the physical connection is broken when the connector is disassembled.
29. A connector according to claim 28, wherein the female component comprises means for latching the male component into position within the female component.
30. A connector according to claim 28, wherein the female component comprises an electrical connector which can be raised or lowered within the female component to make an electrical connection across the connector when the male component is latched into the female component.
31. A connector according to claim 30, wherein the movement of the electrical connector within the female component causes latching of the male component into engagement with the female component and subsequently engagement of the electrical connection between the male and female components.
32. A connector according to claim 28, wherein the means for establishing a physical connection between the male and female components is provided externally on the components and the means for establishing an electrical connection between the components is provided internally on the components.
33. A connector according to claim 28, wherein the means for latching the male component in position within the female component comprises a lever.
34. A connector according to claim 33, wherein the lever is biased either in the inwards or outwards direction.
35. A connector according to claim 34, wherein the bias is movable from the inwards to the outwards direction.
36. A connector according to claim 35, wherein the lever is locked in the inwards biased position.
37. A connector according to claim 36, wherein during release of the connector the bias on the lever is reversed during downwards movement of the means for establishing an electrical connection.
38. The connector of claim 1, wherein the power or control systems infrastructure is a subsea infrastructure.