Visible and NIR Static Target Projector (STP) Types and Specifications
Meridian visible and near infrared STPs are fixed focus optical target projectors that provide a virtual object for accurate image quality testing of cameras. STPs are available as standalone devices or integrated as clusters in Meridian Starfield systems. Optikos STPs are known for using precision machined components and proprietary assembly techniques that ensure accurate boresighting of the target to the outer barrel, and we use our ColliMeter™ technology for measuring collimation to set the object distance to the desired value – infinity or closer. Because of the precision with which boresighting, collimation, and target clocking are set, visible and NIR STPs must be factory configured.
STPs are designed to provide a smooth user experience and minimize the effort required to start testing. The brightness of each unit is linearly controlled by an embedded microcontroller that may be programmed to simply turn on a preset level while also responding to instructions issued over a daisy-chained serial bus. A single interface box can control a large number of STPs in series, each of which is assigned a unique address within the assembly. Factory calibration data for the source is stored within the device, so everything is plug and play. Machined features on the barrel make installing and removing the STPs simple and repeatable.
STPs are offered in a range of clear apertures and Effective Focal Lengths (EFLs) to accommodate a wide range of cameras. The LED source can be configured with various LED color temperatures or NIR and visible wavelengths. The standard target option is a high contrast, crossedge target but custom targets are available upon request. When built into a full-field Starfield configuration, STPs located off-axis can be assembled with pre-distorted targets (designed with a proprietary method) to reverse the lens distortion and produce a slanted edge image that will provide accurate MTF results even with large distortion values.
STPs can be sold individually to be integrated into each customer’s test setups, or can be sold as part of a Meridian Starfield camera test system. When sold individually, STPs are usually shipped with the following accessories:
- USB Interface box and 9VDC power adapter for establishing RS-485 + power bus
- USB Cable for computer connection
- 2-Meter long power + RS-485 bus cable from STP to interface box
- Benchtop cradle stand
- Thumb drive with demo control application, manual, and instruction set documentation
- Storage case
| STP Model Type | STP-035 | STP-050 | STP-075 | STP-080 | STP-102 | STP-175 |
| Nominal focal length (mm) | 35 | 50 | 75 | 80 | 102 | 177 |
| Clear aperture (mm) | 11 | 23 | 23 | 38 | 24 | 45 |
| Standard target pattern diameter (mm)
Custom options available |
9.5 | 9.5 | 5.6 | 14 | 10 | 24 |
| Standard target diameter (°) | 15.5 | 10.8 | 4.3 | 10.0 | 5.6 | 7.8 |
| Typical working distance (mm) | 30 | 70 | 140 | 140 | 120 | 200 |
| Mechanical boresight (°) | <0.05° (for targets with defined center features) | |||||
| Target geometries | Orthogonal crossedge (standard)
Predistorted crossedge Single edge Crosshair |
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| Target contrast ratio | 1000:1 (standard)
4:1 (optional) |
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| White LED source CRI options | 4500K or 6500K (standard options)
3000K, 3500K, 4000K, 5000K, 5700K or NIR LEDs available |
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| LED color options | 635nm, 940nm typical. Enquire about other options. | |||||
| Source lifetime | >50,000 hours @ 50% | |||||
| Interface bus | RS485 (9600 baud), 9VDC | |||||
| Power Supply Input Voltage | 100 to 240 VAC | |||||
| Operating Temperature | 10-40 °C | |||||
| Operating Humidity | 30-60% (non-condensing) | |||||
These examples show popular configurations for each STP Family. Many other options are available – contact sales@optikos.com for more information
STPs can be provided as standalone target projectors or as part of a Meridian Starfield system. Optikos product engineers are available to discuss your requirements and configure an appropriate solution for your unique metrology needs.
