Collimating Lens Attachment — US$95.00
The Collimating Lens Attachment (aka Transmission Sphere) slides into the 1.25″ inside diameter of the SPPDI® 2″ Telescope Adapter. The Collimating Lens Attachment comprises a commercial 1.25″ eyepiece extender tube, with an achromatic collimating lens installed in the narrow end, and an empty RMS-threaded microscope objective holder installed in the opposite end. The output collimated beam has a diameter of about 1/2″, which is presented at the rear aperture of the user-supplied microscope objective.
Output beams with a variety of focal ratios may be produced, depending on the numerical aperture of the microscope objective. Please see Calibration Optics for a description of the microscope objectives available from Kerry Optical Systems. Customer-owned RMS-threaded microscope objectives may also be be used.
When combined with a microscope objective, this attachment serves as a “transmission sphere.” When used as a transmission sphere, the output beam may be used for interferometry of a “fast” (<f/4) converging diffraction-limited or near diffraction-limited spherical wavefront. Converging aspherical wavefronts cannot be measured with this attachment due to retrace errors. As noted previously, spherical or aspherical converging wavefronts “slower” than f/4 may be measured directly, without the need for a transmission sphere.
Orders can be initiated by contacting Kerry Optical Systems by phone or email. Please see our Payments page for instructions.
