APQ 110/550 Fluorite Wide Field Polychromat

Comparison between APQ 110/550 Wide Field Polychromat, APQ 100/640 Quadruplet Polychromat and Carl Zeiss APQ 100/640 Apochromat: Strehl Ratio vs. Wavelength (365 nm – 1014 nm)

The APQ 110/550 Fluorite Wide Field Polychromat shows no drop in Strehl ratio toward or below the diffraction limit at the edges of the visual spectrum, unlike most apochromats.

Thanks to its polychromatic correction, the ten-element CaF₂ optical system of the APQ 110/550 maintains diffraction-limited resolution to the edge of the unvignetted Ø67.4 mm image field (IMX411 image diagonal: 66.7 mm), while utilizing the full UBVRI spectral range (365 nm – 1014 nm) of modern electronic sensors (CCD, CMOS).

Across the entire 365 nm to 1014 nm spectral range, the RMS spot radius remains well within the Airy-disk diameter even at the edge of the Ø67.4 mm image field.

We source specially specified, high-quality fluorite blanks from a certified manufacturer that also supplies CaF₂ raw material to leading precision optics manufacturers for stepper lenses used in VUV photolithography.

The surfaces of the optical elements, made from three different special optical glasses from SCHOTT^® or OHARA^® and CaF₂, are precision machined; one lens surface is aspheric.

Because every manufacturing process has finite precision, even state-of-the-art CNC machining is subject to tolerances. All manufacturing parameters must therefore be carefully specified and toleranced.

A final system correction by a master optician with decades of experience ensures the required high image quality.

A newly developed compensation cell ensures that the elements of the oil-spaced optical system with air gaps remain securely positioned as the temperature changes.