The Westboro Photonics WP6 series of imaging colorimeters is offered with a choice of 9- or 12-Megapixel cooled CCD sensors. WP6 imaging colorimeters are ideal for demanding applications requiring electronic lens control or an integrated spectrometer (both optional), as well as a thermoelectrically-cooled CCD sensor which enhances low light level sensitivity. A WP6 colorimeter can be used to test automotive and avionics displays and controls, vehicle exterior and interior lighting, near-to-eye displays, flat panel displays, the lit area uniformity of lighting products and the projected beam pattern analysis of lamps and LEDs. With an optional conoscopic lens, a WP6 colorimeter can also be used to measure the view angle performance of displays.
The Westboro Photonics WP690 and WP6120 are high performance imaging colorimeters based upon a thermoelectrically cooled CCD sensor with 9.1 or 12 Megapixels respectively. The Peltier-cooled sensor minimises noise and drift and provides an enhanced sensitivity of less than 0.0001 cd/m². When combined with the > 1,000,000:1 dynamic range, this makes the WP6 suitable for use in both high brightness and low light level applications. Integrated into the camera housing is a motorised filter wheel that contains the tristimulus XYZ filters that allow the WP6 to function both as an imaging colorimeter and as an imaging photometer.
The Westboro Photonics WP6 series imaging colorimeters are available in the following versions, with a choice of 9.1- or 12-Megapixel cooled CCD sensors, manual or software-controlled electronic lenses and the option of an integrated spot spectroradiometer. The standard tristimulus filters can be supplemented by radiometric and scotopic filters.
|Model||Sensor (MP)||Electronic Lens Control||Integrated Spectrometer|
The following photometric parameters can be measured using a WP6 series cooled CCD imaging colorimeter:
Each colorimeter has a lens that is matched to the sensor resolution and size, providing optimally crisp and clear images. By matching a lens to a particular sensor, the images created using a Westboro colorimeter can be of a higher quality that supposedly higher resolution cameras without matched lenses. Standard lenses feature focal length between 14 and 100mm. Microscope lenses are available for pixel-level analysis, while near-to-eye lenses are also available for testing the displays on wearable AR devices. A conoscopic lens is also available that allows for the view angle performance of a display to be measured.
The WP6E and WP6ES models feature electronic control of lens focus and iris position. These motorised lenses offer improved accuracy, precision and convenience for all applications.
Display View Angle Testing
The available conoscopic lens accessory enables viewing angle measurements of flat panel displays and backlights. In addition, the system provides 0.05° resolution and 0.0001 cd/m2 photometric sensitivity.
AR/VR Display Testing
The Near-Eye Display (NED) lens option provides optimal test performance for virtual images up to 60° horizontal or vertical field of view (FOV). The periscope design ensures the lens readily fits into the final assemblies of glasses, headsets and helmets. Under different stimuli, human visual accommodation results in varying pupil diameters. Therefore, the entrance pupil aperture is adjustable from 1.5 to 5.0mm.
The WP6ES model benefits from automatic colour correction and radiometric transfer courtesy of an integrated spot spectroradiometer. For the imaging colorimeter models, the camera’s accuracy is improved to the level of the spectroradiometer by automatic correction. For the imaging photometer models, the spectral data also provides radiometric information and other measurement insights.
Using a simple moving mirror and a large fibre guide, a circular area in the centre of the lens’ focal plane is directly coupled to the spectrometer. Compared to beam splitter designs, this setup has higher image quality, better throughput and minimal polarisation dependence.
Radiometric & Photometric Capabilities
Upon request, a WP6 series imaging colorimeter can be factory configured with an additional radiometric filter, which provides for measurements of irradiance and radiance. The radiometric filter extends the wavelength sensitivity of the camera to that of the CCD sensor, 350-1000nm. Calibration of the imaging radiometer must be performed by the user with reference to a spot spectroradiometer which is used to measure the output from the device under test. The WP6 can also be equipped with a scotopic response filter which allows for luminance and illuminance measurements to be performed matched to the dark-adapted response of the human eye.
Photometrica® software and optional software packages provide extensive options for measurement and analysis. The software development kit (SDK) allows for the creation of fully customised solutions using built-in scripting or external control.
Westboro Photonics is an ISO/IEC 17025:2017 accredited calibration laboratory, being the first company in the world to be accredited for the calibration of imaging light meters, as distinct from spot photometers.
An imaging colorimeter is a powerful camera-based instrument that provides for vastly increased productivity compared with ‘spot’ luminance meters. Imaging photometers and colorimeters find application with automotive and avionics displays and controls, vehicle lighting, near-to-eye displays, flat panel displays, lit area uniformity of lighting products and with projected beam pattern analysis of lamps and LEDs. The more common applications include testing of the following products: