Optical Surfaces says it has established an international reputation for the supply of high performance beam expanders for atmospheric Lidar measurements
Lidar (light direction and ranging) is a laser remote sensing technique widely used in atmospheric research to obtain measurements of aerosol particles, pollutants, clouds, temperatures and water vapour.
Lidars are valuable instruments for atmospheric research because they provide an active remote sensing technique that can probe atmospheric regions inaccessible to other instruments, and at high spatial and temporal resolution.
In a Lidar system a powerful laser transmits a short and intense pulse of light.
The pulse is expanded to bring the beam within health and safety requirements and to minimise its divergence, and then is directed by a mirror into the atmosphere.
As the pulse travels upward it is scattered by atmospheric consituents and aerosol particulates.
Light that is backscattered in the field-of-view of a co-aligned telescope is collected and channelled toward detectors by a fiber or other optics.
Satisfying the high performance and design compactness required in Lidar systems is best achieved through an off-axis parabolic beam expander.
Manufactured to better than lambda/10 surface accuracy, the off-axis design of OSL beam expanders produces no central obscuration and highly efficient transmission is obtained, unspoilt by spider diffraction patterns.
Alignment aids are supplied with each beam expander to ensure correct beam pointing.
The all-reflecting design of OSL beam expanders is achromatic and with aluminium coatings can operate from the UV to far IR without adjustment.
Using zero expansion glass mirror substrates OSL beam expanders provide high operational stability.
Lidar systems using OSL beam expander optics are currently being used for pollution detection and characterisation; dynamic measurement of wind speed and atmospheric temperatures; climatic measurement of clouds, aerosols and water vapour ; ozone depletion measurement and high altitude quantitation of trace metals.
Optical Surfaces ISO 9001-2000 approved manufacturing facility provides the flexible resources to supply from single specialist requirements to OEM quantities.
All Lidar beam expanders are provided with a complete quality test assurance report.
