Autocollimators

Collimators

VISUAL OPTICAL INSTRUMENTS

Autocollimators

We offer autocollimators with fixed or variable focus setting as well as with straight, 90° and 60° viewing (only with fixed focus setting). Versions with reticle changer, integrated CCD camera mount, mechanical (MD) or digital double micrometer (MDD) are also available.

Vermont Photonics Autocollimators

Selection Criteria

The high variability of the autocollimators of MÖLLER-WEDEL OPTICAL GmbH allows you the perfect choice for your application. The topics below describe the influences of focal length of objective and eyepiece, objective aperture, fixed or adjustable focus setting and furthermore geometrical or physical beam splitter on the autocollimator.

Focal Length Selection Autocollimators

Depending on the magnification of the instrument a longer focal length of the objective leads to a greater measuring sensitivity and measurement accuracy. As the focal length increases, the measuring range (FOV) decreases proportionally. Additionally, the intensity of the light bundle received by the telescope decreases with increased focal length. A longer focal length affects the mechanical extension of the tube, as well.

In contrast to the usually used eyepiece with f=14.7 mm an eyepiece with f=10 mm gives a larger magnification but lesser image field and eyepiece f=25 mm gives a smaller magnification but larger image field.

Note: After removing the eyepiece cover ring all eyepieces can be upgraded with a C- Mount Adaptor to connect a CCD-Camera to the eyepiece.

Autocollimators Eyepieces Selection

Light conditions are more favorable when large apertures are used, and the evaluation of the results is easier and more accurate. A long distance between mirror and autocollimator or a partially reflective surface demands a relatively large free aperture (or aperture ratio). For these kinds of measurements a relatively large aperture diameter should be used.

The measurement of the angles of plane mirrors in autocollimation is made with a parallel, or infinity focus, beam. Fixed, infinite focus is generally the best choice. For measurement tasks requiring an adjustable focal distance, use an objective tube with focus adjustment. Fixed focus tubes set at other than infinity can also be ordered.

The geometrical beam splitter results in smaller image angles, but greater image brightness and less stray light. These autocollimators are used mainly with small targets. Due to their internal layout, these autocollimators cannot be used for measurement of triple mirrors or corner cubes. In most cases an autocollimator with physical beam splitter is recommended due to the larger measuring range of this configuration.

Note: Geometrical beam splitters are only available for the AKG-eyepiece as modular component (Art. No. 219 035)

Questions about Selection Criteria? Get in touch.

Autocollimators with Fixed Focus Setting

At autocollimators with fixed focus setting the distance between reticles and objective is fixed. Usually the adjustment is made for infinity at a wavelength of 546 nm. Adjustment to other fixed distances or wavelength is also possible on demand.

Straight Viewing Fixed Focus

The simplest version of an autocollimator is an autocollimator with straight viewing. Autocollimators of this version are available with different focal lengths and tube diameters. An autocollimator with straight viewing has the user´s line of sight co-linear with the objective axis. These autocollimators are preferably used in horizontal direction, where the eyepiece is at eye level. In a down-looking arrangement or on optical table 90°- or 60°-viewing is often more suitable.

Fixed Focus with Micrometer

Autocollimators with straight viewing are also available with mechanical double micrometer (AKG MD) and with digital double micrometer (AKG MDD).The Type AKG MD with mechanical double micrometer allows the measurement of tilting angles in two directions. The lateral movement of the eyepiece reticle in x- and y-direction in the image plane can be read from the scale of the micrometer drums. The scale division is 5 micrometer. The Type AKG MDD has programmable measuring gauges, which allows the operator to read the angular displacement in arsec or mrad.

Brochures and Flyers

90° Degree Viewing Fixed Focus

90° Viewing Autocollimator

Another simple version of an autocollimator is an autocollimator with 90° viewing. The user’s line of sight is at 90° to the objective axis. These kinds of autocollimators are used for vertical set-ups or for set-ups on optical tables or for applications where straight viewing is not feasible.

90° Viewing with Reticle Turret

An autocollimator with a reticle turret provides 6 selectable collimator reticles. The reticle turret allows a quick change of reticles for different measurement tasks.

90° with CCD-Camera Mount

The principle, function and layout resemble the autocollimator with 90° viewing. The eyepiece and eyepiece reticle are replaced by a mount for a CCD-camera and the autocollimation image is directly imaged on the CCD-chip when the camera is mounted. With no eyepiece reticle the displacement of the return image is measured on a video monitor or using a computer and software.

90° Viewing with Micrometer

Autocollimator with 90°-viewing is also available with mechanical double micrometer (AKR MD). This type AKR MD is used if a straight viewing telescope cannot be used from ergonomic point of view. It allows the measurement of tilting angles in two directions. The lateral movement of the eyepiece reticle in x- and y-direction in the mage plane can be read from the scale of the micrometers. The scale division is 5 micrometer.

60° Degree Viewing Fixed Focus

The autocollimator with 60°-viewing is also available with mechanical double micrometer (AKW MD) and with digital double micrometer (AKW MDD).

The Type AKW MD with mechanical double micrometer allows the measurement of deflection angles in two directions. The movement of the eyepiece reticle in x- and y-direction in the image plane can be read from the scale of the micrometer drums. The scale division (SD) is 5 micrometer.

The Type AKW MDD has a programmable measuring gauge, which allows the operator to read the angular displacement in arsec or mrad.

Autocollimators with Adjustable Focus Setting

Measuring tasks requiring different wavelengths of light or measurements requiring variable focus (finite and/or infinite) are best accomplished using focusable autocollimators. With the aid of the tube extension the position of the reticles in respect to the focal plane of the objective is changeable. As a result of that the former parallel beam converts into a convergent or divergent beam and yields a real or virtual image of the reticle.

Straight Viewing Adjustable Focus

The simplest version of a focus adjustable autocollimators is the autocollimator with straight viewing.

Vermont Photonics offers autocollimators with adjustable focus setting with different focal lengths, diameters, eyepieces and adjustment ranges.

Adjustable Focus with Micrometer

Autocollimators with straight viewing and adjustable focus setting is also available with mechanical double micrometer (AKGV MD) and with digital double micrometer (AKGV MDD). The Type AKGV MD with mechanical double micrometer allows the measurement of deflection angles in two directions. The movement of the eyepiece reticle in x- and y-direction in the image plane can be read from the scale of the micrometer drums. The scale division (SD) is 5 micrometer. The Type AKGV MDD has programmable measuring gauges, which allows the operator to read the angular displacement in arsec or mrad.