Image Processing Assembly
The Gamma Scientific Image Processing Assembly (GS-IPA) is a precise angular position and luminance measurement combination designed to measure Head Up Display (HUD) and direct view Multi-Function Displays (MFDs) with a built in touch screen graphical user interface.
- Head Up Displays (HUD)
- Direct View Multi-Function Displays (MFDs)
The calibrated mechanical component of the Transport utilizes two motor/disc assemblies on the horizontal and vertical axes to control the pitch (altitudinal) and yaw (azimuthal) angles of the thermally stabilized CCD sensor imaging photometer as it is oriented to view and measure angular position as well as luminance of symbology on HUD, CRT or LCD display images.
The motor drive assemblies in the pitch and yaw axis motion have integral high precision absolute angular encoders that allow automatic operation where an internally stored test macro can be loaded, executed and move the Imaging Photometer in a pre-programmed test pattern that typically over-samples the display image in all areas of interest.
The Image Acquisition System (IAS) portion of the instrument consists of a high-resolution temperature controlled CCD sensor coupled to an adjustable focus optical system that allows focusing from 0.8 meters (30 inches) to infinity, allowing measurements of both HUDs and MFDs.
The precise control of the angular position afforded by the motor drives, absolute angular encoders, and the CCD sensor within the IAS allows the GS-IPA to function as an automated theodolite.
In addition, the detector has been tested to have zero defective pixels, tested and corrected for photometric linearity, and each pixel of the detector is calibrated using an ISO/IEC 17025 accredited laboratory standard of spectral radiance to provide low uncertainty display luminance measurement results.
The central square of the CCD sensing area can be set from 0.01 degrees to 2 degrees in size to define the luminance measure aperture. The GS-IPA can be considered an “imaging micro-photometer” as well as an automated theodolite.
The CCD sensor sits in the IAS’s internal focus transport, which has two inches of travel and enables both manual and optional auto focus capabilities. The auto focus feature of the IAS can be important if the display image being tested is not actually at infinite focus. Most image characteristics are best quantified with the IAS automatically focused on the actual image.
The built in Auto Collimation capability of the IAS assures that precise setting of infinite focus can be set and verified as well as allowing existing HUD holding fixture alignment tooling to be used, greatly reducing the cost of deployment of the GS-IPA to replace existing theodolite based HUD testing solutions.
The IAS is equipped with a photometric filter and additional attenuation to provide a luminance dynamic range of 10,000 footlamberts (34,260 Candelas/m2) to 0.1 footlamberts (0.34 Candelas/m2) utilizing the internal 16 bit analog to digital converter and automatic exposure time determination that provides linearity corrected values. The calibrated values are valid over the full range of focus of the IAS, including the addition of supplemental lenses.
|Image Processing Assembly Specifications|
|Default Luminance Aperture||Square; 0.01° – 2°|
|Luminance Range||0.1 to 12000 footlamberts (1/pi*cd/ft²)
0.1 to 41112 cd/m²
|Angular Subtense/Pixel||0.001734°; 0.10405 arc min; 6.243 arc sec|
|Image Sensor Size||2750H x 2200V pixels|
|Pixel Size||4.54 micrometers|
|Image Field of View||4°|
|Focus Range||80 cm (30 inches) to infinity|
|Luminance Uncertainty*||200 to 3500 footlamberts (1/pi*cd/ft²) +/-5%
58 to 1021 cd/m²+/-5%
3500 to 12000 footlamberts (1/pi*cd/ft²) +/-7%
1021 to 41112 cd/m² +/-7%
|Luminance Repeatability*||3500 to 12000 footlamberts (1/pi*cd/ft²) +/-2%
1021 to 41112 cd/m² +/-2%
|Measurement Accuracy, Azimuth & Elevation||<4.5° = +/-0.1mRad (+/-21 arc sec)|
|Measurement Accuracy, Azimuth & Elevation||< 10° = +/-0.2mRad (+/- 45 arc sec)|
|Measurement Accuracy, Azimuth & Elevation||< 15° = +/-0.3mRad(+/- 63 arc sec)|
|Measurement Accuracy, Azimuth & Elevation||> 15° = +/-0.020mRad/deg (+/-4.2 arc sec/deg)|
|Movement Range||±15° elevation ±30° azimuth|
|Maximum Angular Speed||10 deg/sec|
|Optical Centerline Height||23.65 cm (9.31 inches)
33.3 cm (13.12 inches) with F-16 IAIS platform
|Hardware Verification||Less than one minute|
|Boot Time||Less than one minute|
|AC Power Input||Universal power supply; 100-240V, 50-60Hz|
|Communication Interfaces||(2) RS232; (2) 1Gbs Ethernet; (4) USB|
|H x W x D Without Display Attached||39.4 x 25.4 x 27.9 cm (15.5 x 10 x 11 inches)|
|H x W x D With Display Attached||39.4 x 25.4 x 41.9 cm (15.5 x 10 x 16.5 inches)|
|H x W x D With Display and Platform Attached||49.3 x 25.4 x 44.5 cm (19.4 x 10 x 17.5 inches)|
|Total Weight||17.28 kg (38.10 lb)|
|Display with Mount Weight||5.95 lb|
|Power Supply Weight||.80 kg (1.75 lb)|
*Illuminant A source over the focus range without supplemental lens uncertainty coverage factor 2.
**The information contained in this data sheet is based on Gamma Scientific’s internal evaluation and is subject to change at any time without notice.
|Image Processing Assembly Environmental Specifications|
|Ambient Temperature||5° C to 40° C|
|Non-Operating Temperature||-20° C to 65° C|
|Ambient Relative Humidity
|5% to 95%|
|Operating||0 to 6,000 feet|
|Non-Operating||0 to 20,000 feet|
|Frequency Range||Double Amplitude|
|5 to 15 Hz||0.06 inch|
|15 to 25 Hz||0.04 inch|
|25 to 55 Hz||0.02 inch|