Imaging Lenses - Telecentric lenses
Contrary to the human eye, telecentric objectives have an intake pupil placed in the infinite plane. They are mainly used in microscopes and measurement technology, e.g., in optical micrometres. But projecting systems like profile projectors and photo lithography systems for semiconductor and micro-system technology also require telecentric objectives.
Telecentric lenses are designed with an entrance pupil placed in infinity. Compared to entocentric lenses, only parallel principle rays are imaged through the lens. This ensures a constant magnification for the entire depth of field.
Specifications of our lenses, e.g. about distortion or resolution, are according our datasheets, which are available at the download section of the product tables.
Our standard lenses are just an idea of the various adjustment possibilities. Please let us know your requirements.
Fixed and variable aperture stop
Most lenses from Sill Optics are supplied with a variable aperture stop. This provides the advantage to adjust the luminance, resolution and depth of field of the application. Lenses with a fixed aperture stop are indicated with a blue dot. As some lenses are exposed to vibrations or fast motion, we offer the variable aperture stops to be exchanged by a fixed aperture stop. The size of the fixed aperture stop can be defined by a lens with variable aperture, which can be rented beforehand.
The combination of a telecentric front illumination with the imaging lens is possible for most of our lenses. These coaxial illumination versions are available with a fixed LED of various wavelengths (blue, green, red) or with Ø 8mm fiber /spot port or Ø 6mm fiber port. The part number changes from S5LPJxxxx to S5LPLxxxx.
Variable working distance and magnification
Sometimes suitable lenses do not meet the desired working distance for the planned setup. In most cases adjustment to your requirements is possible. Please contact our product and project managers. Modification of the working distance usually results in modified magnification. Thus adaption of the magnification is also possible.
Variable sensor mount
The lens mount is determined for each lens, but adjustments are possible. With a variety of available adapters or individual solutions threads and mounts for most lenses can be customized.
Due to limited installation space or specific measurement circumstances, an imaging lens might be in a tilted position towards the object. To compensate the resulting blur and deformation in the image, the lens can be mounted to the sensor with a compensating angle. As the compatibility of the lens to the measurement setup depends on various factors (sensor size, viewing angle, magnification, resolution,... ), Sill offers suitable adapters on demand.
For lenses which are exposed to severe vibrations or are placed inside moving parts of machines a glued version is recommended.
Extended wavelength ranges
Most Sill lenses are designed for waveband 450nm – 700nm in the visual spectrum. Thereby monochromatic applications (narrow-banded illumination, black-white sensors) and polychromatic applications (broad-banded or white illumination, color sensors) are possible. Moreover there are special lenses for the UV- and NIR-range available.
In case of special requirements please contact us for a compatibility check to your specifications.