OATi's proprietary CalcuLens™ Beam Deviation application extends existing LAS capabilities to provide the user with a simple, cost effective means for determining beam deviation in an optical assembly of interest.
Traditional beam deviation solutions require pains-taking alignment of a laser in transmission mode through a lens or lens assembly. Any alignment errors of the transmission laser will result in over or under estimation of beam deviation. Alternatively, OATi has designed a precision chuck with a mirror at its base, such that light from the LAS Optical Module makes a double pass through the lens assembly. The laser beam propagates through the lens stack, retro-reflects off the mirror and returns through the assembly, back to the camera in the Optical Module.
The light accrues angular deviation as it passes through misaligned lenses in the assembly. By analyzing the exit angle of light from the double pass , the application calculates the single pass beam deviation to an accuracy of < 10 arcseconds using the standard 90 mm WD objective on typical optics. This cost-effective measurement technique is done solely in reflection, without requiring tilt and centration measurements of individual lenses within the assembly. The CalcuLens™ Beam Deviation application uses LAS technology to offer a quick and effective beam deviation measurement to characterize the global misalignment of an optical assembly .
Schematic diagram showing the principal used in CalcuLens™ Beam Deviation application.
Light from the LAS enters the optical assembly with θ0 = 0
The light with accumulated angular deviation due to lens misalignments exits the assembly with angle θ’ (the beam deviation angle).
The light reflects off the chuck mirror and re-enters the assembly
The light having accrued more deviation on its double pass exits the assembly with angle θf
The Calculens™ Beam Deviation application measures θf and calculates θ’ from a known relationship found through ray-trace.
Click HERE to download our white paper, "Using the LAS to Determine Beam Deviation"