Long Range Testing

For lenses that focus out at long distances, to verify ability to focusing on distant objects you will need a target system that produces an image that is at or beyond the hyperfocal distance of your lens. You can use our chartfinder utility to determine the size of your imaging plane at a distance based on your lens’ angular field of view.

Virtual Target Projection Systems

120° Collimator Lens

A collimator lens (also known as a close-up lens or relay lens) can change the distance at which an object appears. These optics along small high-precision test targets and light sources can produce a virtual image which appears as if it is at a long distance.[1] 

Imatest offers a range of collimator products which can be can be configured to test fields of view between 1° and 180°.

Precisely aligning the test chart with the collimator and the unit under test so that all parts are aligned on a single optical axis becomes the challenge with this solution. Any lens system will focus best in the center, and the on and off-axis quality of the conversion lens affects the measurements that you obtain. This means that the measurements you take, and how they are compared to any of the pass/fail requirements will need to be adjusted to consider the loss of resolution due to the collimator. 

1-10° Target Projection Collimator

In order to verify long-range focusing, collimators are key components of manufacturing equipment which operates in a factory environment. Imatest and our network of partner companies have the optomechanical engineering expertise to provide you with a complete testing system that fits your product.

Collimator Fixture

The Imatest Collimator Fixture can test your imaging system at distances up to infinity within the limited space of a test lab. The Fixture is configurable to your working distances and fields of view with an adjustable lens-to-chart distance, interchangeable collimating lenses, and charts. This relay lens system is ideal for R&D.

The Collimator Fixture integrates with Imatest LED Light Panels, sizes C through G, and includes a joystick and computer-control interface for automatic positioning using four motorized stages as well as storage and recall of device positions. 

For more information, pricing, and current lead time, contact sales@imatest.com 

Download PDF Info Sheet

Projection Collimators

The CM10120 system allows users to simulate a test distance from 1m – infinity. This is useful for testing camera systems that have long focus distances since lab space and production line space are usually limited. The simulated distance (i.e. object distance) is manually adjustable across the entire range. The CM10120 is not intended to fill the camera FOV for most camera systems. The target projected by the CM10120 can be used for testing a given region of the camera FOV, making it useful for tasks such as setting focus or checking for pass/fail criteria. Multiple units can be configured to project multiple targets into a camera if simultaneous multi-region testing is required.

Multi-collimator systems

For wide FoV lenses, it becomes more difficult to cover all the locations on your lens which you are interested in testing. So several collimators may be used that are directed into your lens. 

 

 

Imatest Collimator Fixture VP K50/40 CM10120
  • Designed to fill camera FOV (up to 120º DFOV)
  • Motion stages for camera positioning and distance control
  • Can simulate distances from 400mm – infinity
  • Controlled by onboard computer with easy-to-use interface
  • Accommodates a wide range of targets
  • ILP available in a range of color temps
  • Supports VIS or NIR
  • Price: $35k – $50k
  • Projects a target into camera FOV (inspectible FOV of 10º), i.e. does not fill camera FOV
  • Camera positioning done manually
  • Simulates a distance of infinity
  • LED dimming controlled by manual controller
  • Uses high-precision CoG target reticle (SFRreg)
  • Highly precise – high quality optics, construction tolerances, and target reticle
  • Only available in VIS
  • Price: $9,200
  • Projects a target into camera FOV (inspectible FOV of 10º), i.e. does not fill camera FOV
  • Camera positioning done manually
  • Can simulate distances from 1m – infinity 
  • LED dimming controlled by manual controller
  • Uses B&W LVT film target reticle (SFRreg)
  • Useful for testing most camera modules
  • Available in VIS or NIR
  • Price: $5,000

Physical Targets

SFRreg resolution test target

It is possible to assemble large test chart systems, but the process of producing, mounting and protecting a large test chart, and achieving uniform glare-free lighting becomes more costly and complicated as you increase your chart size. Indoor tests require long dark spaces, outdoor tests are complicated by atmospheric distortion[2] and durability[4] of the target.

As your desired test distance becomes longer, filling your camera’s field of view with a single target such as eSFR ISO, SFRplus or Checkerboard can become prohibitive. The SFRreg Imatest Analysis module and SFRreg test chart enable a flexible target that can be automatically detected and rapidly analyzed by Imatest software.

if you are interested in these sort of test targets, contact our charts department at charts@imatest.com or submit our chart finder form with details about your camera system.

Request a Solution


References

[1] J. Pan, “The First Order Optics of Novel Testing Equipment for Compact Camera Module” in Proc. SPIE 7652, International Optical Design Conference 2010, 76521D (9 September 2010);

[2] David G. Sheppard, Bobby R. Hunt, Michael W. Marcellin Iterative Multiframe Super-Resolution Algorithms for Atmospheric Turbulence-Degraded Imagery

[3] Wikipedia Infinite Focus https://en.wikipedia.org/wiki/Infinity_focus

[4] Photo Calibration Targets Terrestrial Test Patterns Used For Aerial Imaging