Below you find a selection of custom calibration products which we have designed and manufactured in cooperation with some of our customers. These targets were made to fulfil special requirements pertaining to FOV, calibration speed, illumination wavelength, or mounting.
Should you be interested in one of these options, please request a quote or contact us and we can discuss your application and recommend the best solution.
The largest group of custom products are specific patterns and sizes that we do not offer in our standard product portfolio. Examples of these are:
- ChAruCo targets with different dictionaries and/or marker ids, enabling multiple boards to be detected simultanously in the same scene.
- Circle/checkerboard targets with unique finder patterns, enabling partial observation and stereo-calibration.
- Deltille grid patterns and other less common targets.
- Single AruCo marker plates for VR and robot calibration purposes.
- MacBeth color calibration targets.
- Proprietary customer designed patterns. We keep these designs confidential of course and can sign an NDA is requested.
For these custom designs, pricing depends mainly on the size of the desired board, and whether camera-ready vector graphics (true to scale, pure vector PDF/SVG with page size equal to board size, text converted to paths) are provided. We gladly assist in preparing or redrawing customer designs for a fee, and always provide a final PDF proof for the customer to verify before production.
For Alu/HDPE composite targets, we offer the highly versatile Mounting Fixture, which can also be bough for existing calibration targets.
We have realised a number of different mounting solutions for our customers:
- Through-holes precisely machined into your targets according to customer's drawing.
- Slotted aluminium frame protecting and stiffening target and providing mounting options.
- Robotic flange adapter machined and epoxy-glued to calibration target
- Cylindrical holes machined to exact depth on backside of target
With active sensors, we offer a specialized substrate which exhibits highly Lambertian reflectance properties across a wide range of the visible and IR spectrum. This avoids coding errors due to reflectance differences. This material is however considerably more expensive and not as durable as our standard product range and is not water resistant. In the images below, a strong ring light was directed at the center of our Lambertian substrate. As seen, the change in viewing angle has no visible influence on pattern contrast, which is due to the Lambertian reflectance property.
Passive Thermal Polymer substrate
For LWIR/MWIR cameras, our standard targets are not ideal because the aluminium substrate has high thermal conductivity and small emissivity contrast. For these purposes, we can provide a target printed onto a substrate with low thermal conductivity and high thermal capacity, ideal for storing thermal energy and emitting thermal radiation contrast.
Large FOV targets
Cameras should always be calibrated with the calibration target at the application’s working distance and also cover a rather large portion of the FOV in each single view. For large FOVs, we can manufacture targets up to 2500x1500mm in size. These need to be mounted into very rigid and flat frame structures. We can design and manufacture these structures for you or just deliver the plate insert.
Pricing depends on size and complexity.
In multi-camera setups, extrinsic calibration can benefit from multiple calibration patterns (network calibration). With a cube structure, the target assembly is very rigid and the individual faces can be accurately calibrated by us before delivery. This allows for quick and accurate extrinsic calibration of multi-camera setups with opposing views.
Patterns can be individually specified. The cube mounts to any standard 1/4''-20 tripod screw.
3D calibration targets
While planar targets are the most common, we have also successfully employed the 3D calibration target design below. This allows accurate and precise calibration from as little as a single image, which is useful for e.g. factory calibration. Uncertainty in parameter estimates would be around 1% for a single image using a single radial coefficient camera model. Currently, this target design is manufactured upon individual customer request. Software code based on OpenCV can also be provided for this target.
Pricing and lead time: very dependent on physical size and individual requirements.
If you are interested in any of these options, please contact us, e.g. by using the request quote form.