SCATTERING MEASUREMENTS
Light Tec offers services such as scattering measurements (BSDF for Bidirectional Scattering Distribution Function) and also provides its own instruments (scattering measurement systems).
Being a pioneer in the optical branch that is the scattering measurement, Light Tec has become an expert in this field and performed a large number of projects over the years. The expertise of our team into the optics field (optical engineers and PhD laser optics) and the quality of our photometric laboratory allow Light Tec to offer the best solutions for our customers.
The measurement activity is an additional service to our optical design software LightTools, LucidShape and Code V. It was first created to build the software libraries in order to help designers with real and accurate data.
On top of that, Light Tec has its own R&D department where the Mini-Diff V2 and REFLET 180S are being developed. Both instruments can be used to do scattering measurement by yourself if you need to analyze lots of samples whatever your applications are.
These devices are also used by our technical team in our photometric laboratory. If you would like a demonstration in our office (Hyères, France), you can ask our team for an appointment.
The R&D department is also responsible for the improvement of the equippment in the laboratory, especially for our high specular measurement system.
Customer’s references: Automotive Lighting, BARCO, Bayer, Bosch, Broadcom, CREE, ESA, Nikon, Osram, Philips, Thales, VARROC, Sordern, Visteon….
MINI-DIFF V2
Mini-Diff V2 is a compact and portable optical system for scattering characterization: measure the BRDF & BTDF of any kind of materials and objects. With Mini-Diff V2 you can measure in a fast and easy way, the luminous energy distribution and consequently characterizes surfaces of your examined regions such as roughness, defects as well as types of coatings or paintings and more.
From the Plug & Play functionality to the technical specifications, Mini-Diff V2 is a great device which allows you to save time and money thanks to the facility to measure and the quality of the results. If you often need to measure samples or surfaces outside the office, Mini-Diff V2 is still the best solution for you!
Mini-Diff V2 is the second version of the instrument including new improvements:
- Measurements of BSDF in red, green, and blue (RGB) and IR at 940 nm.
- TIS measurements for RGB
- Dynamic range has been increased to 105
- Colorimetric data: Lab or u’v’
BSDF Measurement Breakdown:
BRDF is measured for 4 angles of incidence (AOI): 0°, 20°, 40° and 60°.
BTDF transmissive module now measures 4 AOIs.
You can find more technical information in our brochure (see link below).
The Mini-Diff V2 is really easy to use. A measurement takes less than 1 minutes*:
- Plug the Mini-Diff to a computer
- Launch the Mini-Diff software on the computer
- Calibrate the instrument with the calibration standards
- Measure your material
- See the result on the software
- Export the result
*Calibration and measurement for one angle of incidence and one wavelength.
Measurements can be exported to those following format:
ASTM (text) / LightTools ® native / TracePro ® native / Slice Format (intensity) / Gaussian & Lambertian / ABg Harvey Shack models
Measurements can be imported into commercial optical software: LightTools®, TracePro® and more.
The list is available upon request.
Mini-Diff V2 is delivered with its own suitcase which include the calibration standards, the software, the notice and the cables.
EXAMPLES
Please, access to more info on the following examples in details:
- Lambertian standard
- Surface of a table
- Plastic of a credit card
- Anisotropic reflector as Reflector Miro 5
- Diffuser as Luminit Beam Shaper
You can download the Evaluation package with all the examples as reflector, diffuser and paint.
MINI-DIFF VPro
The Mini-Diff VPro is a 3D Hemispherical Scattering Measurement, camera based, to characterize scattering surfaces. Like the Mini-Diff V2, the Mini-Diff VPro provides BRDF, BTDF and TIS measurements for Red, Green and Blue colors (RGB). It also delivers the color data in reflection or transmission.
The measurement system is integrated in one dark box, which decreases stray light in the instrument and temperature deviation during the measurement. This dark box helps to provide a higher stability and a higher precision that the Mini-Diff V2.
This instruments offers, a choice of incident angle on the sample from 0 ° to 60° , motorized, and controlled from the Mini Diff software.
Improvements of the Mini-Diff VPro from Mini-Diff V2 :
- Dark Box included
- Motorized Angle of the Incidence beam from 0° to 60° with a 1° Step
- Better camera than Mini-Diff V2
- Better performance
- BTDF Dynamic increased by 10 from 105 to 106
- One calibration for 12 Hours of measurements is enough (even longer in a Controlled room)
- Angular resolution improved down to 0.5°
Exportation available to ASTM, BSDF, Mesh, Slice, Gaussian / Lambertian fit, ABg format.
Exportation also availbletowards optical simulation software (list available under request).
Mini-Diff VPro is delivered with its Dark Box, calibration standards, the software, the notice and the cables.
You can find more technical information in our brochure (see link below).
You can download our Demonstration Video of the Mini-Diff VPro on the link below
REFLET 180S®
REFLET 180S is a unique stand-alone scattering measurements system.
REFLET 180S is especially suited for back/forward scatter light characterization for all types of materials and objects. It allows you to measure the light distribution contained in the radiation lobe of these materials in photometric and colorimetric terms. Moreover, the system measures BRDF & BTDF which perfectly represents the way any surface scatters incoming light in 3D space.
The accurate analysis of the shape of the radiation lobe surface in terms of roughness, defects (presence as grooves or scratches), ordered microstructures and more. The determination of the spectral composition observed in every direction gives information on the type of paint or covering, and eventually, can characterize the signature of fluorescence, OVI inks, or iridescence with angular variation of colours, and both thin and filtered layers. Lastly, the spectrophotometric cartography of the backscattered light analyses the chemical composition on the surface area of the object for oxidation, dirt, pollution and more.
The system is structured in a modular fashion. It can easily be modified to user requirements, measurement with integrated flux or spectral analysis, or with a white light coloured lighting. The REFLET 180S optical bench is also easy to use as manually for spot inspection or quick analysis.
REFLET 180S allows you to analyse by yourself all samples you need to characterize, with a higher accuracy, exactness and reliability (than Mini-Diff). The device is suited for laboratory uses. It will allow you to get efficient data to import into your optical design software. Afterwards, you will be able to get free time through the production in masked time, as well as earn money, thanks to the quality of REFLET 180S and its analyses that will operate in your final projects!
The instrument is delivered with its dark box.
REFLET 180S software enables measurements exportation to optical design or other illumination software.
EXAMPLES
You can download application notes (pdf) for more information on our system:
| Instruments | Mini-Diff V2® | Mini-Diff VPro® | REFLET 180S® | High Specular |
|---|---|---|---|---|
| Measurement of light Scattering | ARS/BRDF/BTDF | ARS, BRDF and BTDF | ARS/BRDF/BTDF | ARS/BRDF/BTDF |
| Wavelength Light Source | 465 - 525 - 630 nm and 940 nm | 465nm, 525nm and 630nm | Halogen white lamp + passband filter | Discrete values from 280nm to 10.6µm |
| Wavelength Detector Sensitivity | NA | NA | VIS IR 900-1700nm optional Spectrometer [400-800]nm | NA |
| Angles of incidence | Fixed for BRDF and BTDF : 0°, 20°, 40° and 60° | Tunables: For BRDF and BTDF : from 0° to +60° | Tunables : For BRDF and BTDF : from 0° to +90° | Tunables: for BRDF : from 5° to +90° For BTDF : From 0° to +90° |
| Angular range | 3D spherical measurement | 3D spherical measurement | 2D and 3D spherical measurement | 2D spherical measurement |
| Spot Size (diameter) | > 1mm | > 1mm | 1mm to 13mm continous | 2mm to 14mm depending on wavelenghts |
| Observed Area Size | ∅ 1mm | ∅ 1mm | ∅ 6mm /∅ 8mm /∅ 14mm | NA |
| Beam Divergence | NA | NA | +/- 2.26° to +/- 0.15° | +/- 0.01° for visible +/-0.1° for IR |
| Incident beam positioning precision | NA | NA | 0.001° | +/- 0.001° |
| Detector Acceptance Angle | +/- 0.5° | +/- 0,5° | +/- 0.04° / 1.1° / 2° | +/- 0.001° |
| Detector positioning precision | NA | NA | 0.001° | NA |
| Measurement resolution | 1° | 1° | 0.01°/0.1°/1°/10° | 0.001° |
| Global axes aligment | 1° | 1° | < 0.5° | 0.002° |
| Accuracy | < 5% | < 2% | < 1% | < 1% |
| Repetability | < 2% | < 2% | < 1% | < 1% |
| Minimum BRDF | 10e-2 | 10e-3 | < 10e-4 | < 10e-7 (10e-5 for IR) |
| Dynamic Range | 10e5 | 10e6 for BTDF 10e5 for BRDF | 10e9 for visible and 10e6 for IR | 10e13 for visible and 10e9 for IR |
| Minimum signature | +/- 1° for BTDF at 0° at 525nm | +/- 0.5° for BTDF at 0° at 525nm | +/- 0.15° | +/- 0.01° for visible and +/- 0.1° for IR |
| Weight | 2 Kg | 42kg | 80 Kg | NA |
| Dimensions | 10 x 10 x 30 cm | 450mm x 600mm x 738mm | 86 x 98 x 122 cm | NA |
| Advantages | Plug & Play Easy to use & Fast Portable & Compact Attractive cost | High Precision High Stability Easy to use instrument Laboratory version of the Mini-Diff V2 | High dynamic range High precision High repeatability Customisable wavelength range | Very high dynamic range Measurement at 0.02° from the specular High precision High repeatability Customisable wavelength range |
Services
Scattering measurement is also known as BSDF for Bidirectional Scattering Distribution Function. The BSDF determines the surface characterization of materials, objects or all kinds of surfaces through the light dispersion. The measurement can be done in reflection (BRDF) or in transmission (BTDF).
Scattering measurements available from us:
- 2D & 3D BSDF (Front & Back) measurements
- High resolution BSDF
- Spectral BSDF
- TIR (Total Intern Reflectivity) measurements
- TIS (Total Integrated Scatter) measurements
- From UV (280 nm), trough Visible, up to IR 3.39 and 10.6 microns
Our measured data are delivered in text format. Then, all data can be imported in every optical design software!
Light Tec has also developed an refractometer dedicated to the refractive index measurements of optical plastic (PMMA) plates with absolute accuracy of ±0.001 and with high repeatability (better than 1%).
In May 2014, Light Tec moved to a new place and created a new laboratory especially dedicated to measurement.
The laboratory is a black room to avoid any inconvenient stray light and the temperature is controlled and regulated for optimal measurement environment.
We have now a class 100 (ISO 5).
In our laboratory, we do have several instruments : integrating spheres (6”, 8” and 40” inch), two goniophotometers (REFLET 180S), a high specular scatterometer, a lux meter and luminance meter, a spectrophotometer, a videophotometer and many sources, filters and lasers.
Moreover, Light Tec has developed a high specular bench for high specular materials. It is well suited for back/forward scatter light characterization for all types of materials and objects. The system measures BRDF & BTDF which perfectly represents the way any surface scatters incoming light in 2D space.
The project has been also extended with the CNRS for a co-development in infrared wavelengths (3.39 and 10.6 µm).
Today, we can provide wavelengths in the range of UV (280 nm) up to IR (10.6 µm) with a dynamic of 1013.
The system has a resolution to a minimum angle down to 0.02° from the specular and the bench length is about 10 meters.
This system is only available on the measurement service.
Applications:
- High polished mirrors and optics, transparent surfaces (glass, lenses, and crystals) which have very low scattering such as 10-9 sr-1.
- Black materials and coatings with a very low BRDF are really difficult to measure because they absorb almost all the light (99% of absorption).
- For baffles (edge scattering) or structure.
- And more!
Our staff will be glad to answer your technical questions and inform you about pricing.
Our services are available worldwide! Please contact our distributors directly if you are outside of Europe in order to have a quote! Thank you for your comprehension.