Optical coupling devices
AssigneeSelex Sensors and Airborne Systems Limited
InventorRoger Hill
Life of this patent
Estimating the term…
Abstract
A laser transmitter unit is described, the unit including a laser diode 2 emitting laser radiation into a lens system. The lens system includes collimating lenses L1, L3 and focussing lenses L2, L4. Additionally, compensating or steering lens S1, S2 are positioned between the collimating lenses L1, L3 and the focussing lenses L2, L4. The steering lenses S1, S2 act to reduce the sensitivity of the focussing lenses L2, L4 to position within the lens system. The position of the focussing lenses can be difficult to control, particularly when the lenses are welded into position in the laser transmitter unit 1.
Claims20
A method of reducing the sensitivity of an optical device to post-weld drift, the device including a radiation emitter or detector and a lens system including a collimating lens, a focussing lens and a compensating lens, the method comprising the steps of:
- (i) directing an optical beam at the lens system in a first position, such that an output collimated beam is produced;
- (ii) adjusting the position of the collimating lens relative to a source of the optical beam to optimise collimisation;
- (iii) directing the optimised collimated optical beam at a focusing lens to focus the optimised collimated optical beam;
- (iv) adjusting the position of the focusing lens to focus the optimised collimated optical beam onto an output device;
- (v) welding the focusing lens in its adjusted position;
- (vi) positioning the compensating lens in the path of the focused collimated optical beam;
- and
- (vii) adjusting the position of the compensating lens to correct for any errors in setting the focusing lens.
Dependencies are inferred from the claim text.