Compact and Cost-effective for Visible, SWIR and LWIR Lens Measurements
LensCheck™ Systems are a cost-effective solution to your production and prototype lens qualification needs. Optikos, the leader in image quality test equipment, is pleased to offer this compact, efficient, easy-to-use quality control tool. LensCheck™, with patented Optikos® VideoMTF® image analysis software, features realtime MTF testing and analysis enabling manufacturers to qualify incoming products quickly and reliably and minimize the risk of sub-standard complete assemblies.
Applicable Lenses for Testing
| Specification | VIS | LWIR |
|---|---|---|
| Entrance Pupil Diameter | Up to 50mm | Up to 50mm |
| Focal Length | ≤100mm (with appropriate image analyzer objective lens) | 5-50mm |
| f-number of the lens | f/20 to f/1 (with appropriate image analyzer objective) The suitability of fast, non-telecentric lenses at off-axis field angles is determined by whether the image cone falls within the acceptance cone of the image analyzer objective. | f/20 – f/1 |
| Image Format Size | Up to 25mm diagonal | Up to 25mm diagonal |
| Max Spatial Frequency | Up to 500 lp/mm customizable up to 1000 | Up to 60 lp/mm |
Other characteristics that factor into the determination include spatial frequency of interest, chromatic performance of the lens, and departure from telecentricity at off-axis angles. These parameters are seldom independent, making it difficult to place rigid bounds on the space of the lenses that may be tested on LensCheck instruments. However, it is generally true that lenses that fall within the bounds described above are usually good candidates for testing with this instrument. There may be special cases in which lenses within these bounds may not be suitable for testing, and there are certainly cases in which lenses outside of these bounds may be tested. When in doubt, consult an Optikos engineer for advice.
- MTF – On/Off Axis
- EFL and f-number
- Back Focal Length
- Astigmatism
- Field Curvature
- Distortion
- Chief Ray Angle
- Transmission (VIS option – requires optional Transmission Kit)
- Stray Light (VIS option – requires optional Stray Light Kit)
- Axial Chromatic (VIS option – requires optional Reflective Collimator and Apochromatic Objective Relay Lens)
- Lateral Chromatic (VIS option – requires optional Reflective Collimator and Apochromatic Objective Relay Lens)
- Patented VideoMTF® technology enables real time MTF measurements
- Flexible platform allows a wide range of measurements (e.g. MTF, EFL, Distortion)
- VIS – Industry leading measurement accuracy better than 2% (1% typical); and better than 1% repeatability (0.5% typical)–each validated with 50 mm f/5 Audit Lens)
- LWIR – Industry leading measurement accuracy better than 3% (2% typical); and better than 2% repeatability (1% typical) –each validated with 50 mm f/5 Audit Lens
- Configurable automated measurement routines
- Easily switch between wavebands (VIS/NIR, SWIR, or LWIR)
- Installed in production and R&D facilities around the world
| Measurement Accuracy: | VIS – Industry leading measurement accuracy better than 2% (1% typical) LWIR – Industry leading measurement accuracy better than 3% (2% typical) |
| Repeatability: | VIS – Better than 1% (0.5% typical) repeatability–each validated with 50mm f/5 Audit Lens LWIR – Better than 2% (1% typical) repeatability–each validated with 50mm f/5 Audit Lens |
| Physical Size: | 15″ (355mm) H 30″ (762mm) W 48″ (1219mm) L |
| Power Requirements: | 100 ~ 240 VAC 60/50 Hz Computer 8/5A, monitors 0.6A each, DC power supply 1.6A, light source 2/1A |
| Environmental: | Optimal performance is achieved in a dark room |
| Refractive Collimator: | 355mm EFL, 50mm clear aperture; shorter EFL collimators available upon request |
| Source Module: | VIS – Fiber-optic light source: 400-1000 nm 8-position manual target and filter wheels Target set: pinholes, USAF 1951, and alignment target Filter set: photopic, 546 nm bandpass, infrared cutoff, and RGB set LWIR – Broadband emitter: 7-15 microns 12-position high-speed motorized target wheel Target set: slits, pinholes, crosshairs, and alignment target Filter: 8-12 micron bandpass |
| Image Analyzer: | VIS – Sony EXview HAD CCD II offers improved sensitivity, dynamic range and noise characteristics: 2736 x 2192 pixels Calibrated 40x 0.65 NA achromatic objective 14-bit video output LWIR – Uncooled microbolometer 324 x 256 format Spectral sensitivity 7.5-15 microns Calibrated 7.5x 0.70NA relay lens 14-bit video output |
| Motorized Z-axis: | 25mm travel 0.1 μm resolution |
| Motorized X-axis: | 25mm travel with 0.05 μm resolution glass scale encoder |
| Manual Y-axis: | 12.5mm travel |
| Motorized Lens Platform: | +/- 105° off-axis rotation 0.0001° resolution glass scale encoder 0.5m optical rail Self-centering lens mount |
| Options | VIS | LWIR |
|---|---|---|
| Finite Conjugate Instrument (available as an option or standalone unit) | ✔ | |
| Adjustable Conjugate Instrument (available as a standalone or by customizing existing LensCheck) | ✔ | |
| Stray Light Kit | ✔ | |
| Achromatic Objectives | ✔ | |
| Apochromatic Objectives | ✔ | |
| Transmission Kit / Relative Illumination Kit | ✔ | |
| Rotary Lens Mount–360° | ✔ | ✔ |
| Reflective Collimator | ✔ | ✔ |
| Audit and Reference Lenses | ✔ | ✔ |
| Lens Mounts * | ✔ | ✔ |
* Supplied with standard three-jaw caliper lens holder for lenses with diameters in 5-25mm range. For best results, we suggest using available lens mount for specific mounting interfaces. A partial list of available adapters includes the following: M7 through M12, C-mount, T-mount, etc. Custom adapter plates are available.
Adjustable Conjugate Measurement Instrument
The Adjustable Conjugate Instrument is available as a standalone unit or by customizing your LensCheck. It allows you to measure lenses at any object distance–from -1m to infinity to +1.2m for real object distances; and at any field angle within +/- 100°. The negative conjugates are used for applications such as virtual reality, where the image is formed behind the lens you’re testing.
Finite Conjugate Lens Measurement Instrument (VIS only)
The Finite Conjugate Lens Measurement Instrument is available as a standalone unit, or as a LensCheck™ VIS option. When used as a LensCheck option for measuring finite distances, the LensCheck Image Analyzer (IA), IA Mount, Rail and Lens Mount are removed from the LensCheck unit and mounted to the instrument base. The image may then be moved to a precise location on the rail, and may be moved off-axis. Manual Z-axis: 1000mm travel with 2μm resolution encoder; motorized X-axis
Rotary Lens Mount (VIS and LWIR)
Motorized lens mount accommodates varying diameter lenses
Lens can be measured for centration and optical axis mount.
Transmission Kit (VIS only)
Transmission measurements: Measure sphere irradiance with or without UUT;
Accuracy of 0.1% validated using Reference Lens with uncoated window
Stray Light Kit (VIS only)
Stray Light measurements per ISO 9358; for lenses with focal lengths >15mm (Standard kit, 15mm);
Black dot surrounded by uniform bright field
Validated with Reference Lens down to 0.1%
Read about Stray Light Measurement
Reflective Collimator (VIS and LWIR)
Suitable for testing wide spectral ranges free of chromatic aberration.
Highest precision collimated wavefront quality
Expanded focal length allows for testing longer focal length lens assemblies
Apochromatic Objectives (VIS only)
Infinity corrected 10x, 20x, and 40x objectives with tube lens suitable for spectral broadband testing
