APQ 100/640 Fluorite Quadruplet Polychromat

Comparison between APQ 100/640 Polychromat and Carl Zeiss APQ 100/640 Apochromat: Strehl Ratio vs. Wavelength (365nm – 1014nm)

The Fluorite Quadruplet Polychromat 100/640 does not show any decrease of the Strehl ratio near or below the diffraction limit in the peripheral regions of the visual spectrum, as is the case with most apochromats.

Due to its polychromatic correction, the 100/640 CaF₂ Quadruplet is the first astronomical optics that exploit the full UBVRI spectral range (365nm – 1014nm) of modern electronic sensors (CCD, CMOS).

We source the high-quality fluorite blanks with special parameters in selected quality from a certified manufacturer, which also supplies the global players of precision optical equipment with CaF₂ raw material for the production of stepper lenses for VUV photolithography.

The surfaces of the objective lenses made of three different special optical glasses of SCHOTT^® or OHARA^® and CaF₂ are precision machined, a lens surface is an asphere.

Because every fabrication can only be done with finite precision, even the latest technologies and state-of-the-art CNC precision machining processes are subject to errors. All manufacturing parameters must therefore be tolerated conscientiously.

The required high image quality is achieved by a final system correction, which is performed by a precision optics master with decades of experience in his field.

Thanks to a novel compensation cell, the lenses of the completely oil spaced objective (without air gaps) are held in stable position with fluctuations in temperature.

The thermal equilibrium sets in quickly and rattling of lenses in the cell with all negative consequences is prevented.