innovation highlight

Computer-generated holographic null lenses reference lenses, for ultra-precise quality control of optical surfaces

Modern-day imaging and illumination systems increasingly make use of aspherical optics whose surfaces diverge from purely spherical shapes in order to correct optical errors (chromatic and spherical aberration, astigmatism, etc.). Diffractive Fizeau null lenses (DFNLs) are test instruments patented by DIOPTIC GmbH and specially designed for ultra-precise inspection of such aspherical structures, using conventional interferometric test processes.

$DIOPTICs diffractive Fizeau null lens for ultra-precise surface testing of spherical and aspherical surfaces$

DIOPTICs diffractive Fizeau null lens for ultra-precise surface testing of spherical and aspherical surfaces

The great advantage of DFNLs is that their Fizeau principle ensures undisturbed, error-free measurement. In order to carry out interferometric surface testing with conventional reference lenses, an additional computer-generated hologram has to be inserted into the optical path, risking inaccuracies caused by the hologram substrate. DFNLs, in contrast, actually replace the reference lens and thus significantly reduce the amount of adjustment necessary.

DFNLs produced by DIOPTIC are compatible with all of the most commonly used interferometers. Since they are the only diffractive element in the optical path, it is now possible to measure aspherical surfaces in the same way as spherical surfaces.

Specifications:
? DFNL diameter up to 300 mm
? Mounted on a standard bayonet holder
? Suitable reference lens with integrated generation of reference wavefront
? Integrated alignment hologram allows simultaneous measuring of the vertex radius of curvature of the lens under test
? Measuring precision PV < ë/10 (not applicable to large numerical apertures)
? Standard numerical aperture of DFNL is NA < 0.4

Characteristics:
? Integrated alignment hologram facilitates adjustment of lens under test
? High measuring precision, no measurement artifacts due to the substrate
? No need to align the hologram relative to the interferometer
? No separate holder for the hologram required

Contact:
DIOPTIC GmbH
Kriemhildstraße 11
69469 Weinheim
Phone: ++49 (0)6201-25599 60
Fax: ++49 (0)6201-25599 61
E-mail: info@dioptic.de
http://www.dioptic.de

Topic: Micro-Nano-Opto, Production and engineering, 51ccbe67dba47c94399326aed46ff3a3
Source: CC UPOB
Region: Northern Lowlands

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	innovation highlight Computer-generated holographic null lenses reference lenses, for ultra-precise quality control of optical surfaces Modern-day imaging and illumination systems increasingly make use of aspherical optics whose surfaces diverge from purely spherical shapes in order to correct optical errors (chromatic and spherical aberration, astigmatism, etc.). Diffractive Fizeau null lenses (DFNLs) are test instruments patented by DIOPTIC GmbH and specially designed for ultra-precise inspection of such aspherical structures, using conventional interferometric test processes. $DIOPTICs diffractive Fizeau null lens for ultra-precise surface testing of spherical and aspherical surfaces$ DIOPTICs diffractive Fizeau null lens for ultra-precise surface testing of spherical and aspherical surfaces The great advantage of DFNLs is that their Fizeau principle ensures undisturbed, error-free measurement. In order to carry out interferometric surface testing with conventional reference lenses, an additional computer-generated hologram has to be inserted into the optical path, risking inaccuracies caused by the hologram substrate. DFNLs, in contrast, actually replace the reference lens and thus significantly reduce the amount of adjustment necessary. DFNLs produced by DIOPTIC are compatible with all of the most commonly used interferometers. Since they are the only diffractive element in the optical path, it is now possible to measure aspherical surfaces in the same way as spherical surfaces. Specifications: ? DFNL diameter up to 300 mm ? Mounted on a standard bayonet holder ? Suitable reference lens with integrated generation of reference wavefront ? Integrated alignment hologram allows simultaneous measuring of the vertex radius of curvature of the lens under test ? Measuring precision PV < ë/10 (not applicable to large numerical apertures) ? Standard numerical aperture of DFNL is NA < 0.4 Characteristics: ? Integrated alignment hologram facilitates adjustment of lens under test ? High measuring precision, no measurement artifacts due to the substrate ? No need to align the hologram relative to the interferometer ? No separate holder for the hologram required Contact: DIOPTIC GmbH Kriemhildstraße 11 69469 Weinheim Phone: ++49 (0)6201-25599 60 Fax: ++49 (0)6201-25599 61 E-mail: info@dioptic.de http://www.dioptic.de Topic: Micro-Nano-Opto, Production and engineering, 51ccbe67dba47c94399326aed46ff3a3 Source: CC UPOB Region: Northern Lowlands	Print page Back