Point Source Microscope

Think of the PSM as a Swiss Army Knife for your Lab

Think of the PSM as a Swiss Army Knife for your Lab

Nearly as precise as an interferometer, yet far more flexible and easy to use due to its small size, light weight and powerful software.




Optical alignment means positioning optically significant features like centers of curvatures and foci precisely where the optical design specifies.
The PSM enables this process by detecting and locating these optical features on the micrometer level and then relating them to mechanical fixtures, datums and features such as steel balls.
The PSM bridges the gap between optically significant features that cannot be mechanically probed and mechanical hardware such as bores, seats and mounts that can be located by conventional mechanical means.




The PSM is also valuable for aligning aspheres and off-axis aspheres by using the aberrations aspheres produce when they are misaligned.
The PSM sees the reflected or transmitted Star image produced by the optical element or system in real time so there is optimum visual feedback as adjustments in alignment are made.
Since the PSM is sensitive to wavefront errors of as little as 8th wave rapid adjustment is made to near perfect alignment as witnessed by a symmetric image viewed going through focus.




Picture of PSM aligning an off-axis parabola to a fiber feed using a plane mirror

In addition to its use for alignment, the PSM is useful for incoming inspection for radius of curvature, focal length, figure errors larger than 8th wave and centering errors.

Used as an autocollimator by removing the objective lens, the wedge in windows and parallelism of prism faces can be measured with 1 arc second precision.

The small beam size makes it particularly useful for small prisms.

Note on using PSM with other light sources

We are often asked if the PSM can be used at wavelengths other than the standard internal laser diode and LED sources at 635 nm. The answer is definitely yes by coupling in an external fiber feed light source.

The PSM performs to original specifications all the way from 405 to 1080 nm without any modification.

This makes the PSM useful for aligning laser diode sources to other components in an optical system, for example. The useful spectral range for the PSM may be even greater, we simply have not tried over an even broader range.



The PSM comes as a complete system ready to use as soon as the computer boots. The PSMAlign, LabView based, software is easy to use and the source code is available.
The centroid data is available for external feedback to other systems or the centroid data can be stored for later use.

Full field video microscope images and point source Star images can be saved in png format for later analysis and use.


FAQ: Can the wavelength of the laser diode source in the PSM be changed from the standard wavelength of 635 nm?

Yes, the PSM comes with an internal source whose wavelength is 635 nm which is fiber coupled into the PSM via a FC/APC fiber connector. The internal source fiber can be unscrewed and stored in an adjacent storage fiber connector. An external source is then coupled into the now vacant active FC fiber connector. The external source fiber to the PSM must be terminated with a FC/APC connector for the PSM to work properly.

The beamsplitters in the PSM have broadband coatings so any source from 350 to 700 nm can be used and even beyond with some loss in sensitivity. The Thorlabs S1FCxxx fiber-coupled lasers sources are well suited as are similar sources from qphotonics that provide a wider range of wavelengths. Incandescent sources can be coupled in as well as long as the termination into the PSM is a FC/APC connector. The losses will be large getting the white light in but the PSM is quite sensitive to low light levels.

FAQ: How is the spatial scale calibrated in the PSM?

The spatial scale in the PSM is controlled using the “Calibration Factor” on the Cal Tab. For a 10x objective the Calibration Factor should be about 1.0 and then the units displayed on the right hand side of the PSM2 GUI under Spot will be correct in μm. For a 4x objective the Calibration Factor should be about 2.5.

Many things influence the precise PSM calibration including the pixel size in the camera and the make of the objective lens. For precise calibration of the spatial scale it is best to use a sample of known line width such as a stage micrometer or Ronchi ruling and measure the width using as much of the field of view of the objective as possible.

Use the arrow cursor to click on one edge of the line and then click on the other edge. Green crosses will appear with each click. On the Threshold tab the coordinates of the green crosses are listed. If the distance between the two crosses at either edge of the known line is not correct, change the Calibration Factor by the ratio of the measured value to the known value and repeat the measurement. One or two times making the measurement should get to 1% of the true spatial scale. Note that the coordinates of each cross is with respect to the reference cross.

Once this is done the scales is correct for all readings on the GUI unless the objective or camera are changed in which case the calibration must be repeated. The units on the scale bar and the crosshairs are also controlled by this calibration and will be correct once calibrated. Notice the scale bar at the bottom of the Cal tab. It can be made any length, have any number of divisions and be placed anywhere on the video screen.


Please use the form below to inquire about or purchase.

I want the LCS-PSM Align Software.
Invalid Input
Invalid Input
Invalid Input
Invalid Input

Share this product

Related Products

Case Studies & Testimonials

  • "You are always responsive and give us lots of useful information!!"

    Dr. Shaojie Chen
    Dunlap Institute for Astronomy and Astrophysics
    University of Toronto


  • "As always we are very much loving the instrument, I personally love the camera upgrade from what I'm used to!"

    Weslin Pullen
    Hart Scientific Consulting International, LLC
    Tucson, Arizona


  • The PSM is an ideal tool for finding the center of curvature of a ball or the axis of a cylinder. The question is for how small a ball or cylinder can the PSM do this?

    The smallest article that was readily available was a piece of monofilament 8 pound test fishing line that was 290 μm in diameter. There was no problem finding the axis of the fishline, and separating the Cat’s eye reflection from the surface from the confocal reflection of the axis. The experiment was done with a 5x objective, and the result would have been even more definitive using a 10x objective.

OPG Customers

Worldwide Representatives


OPTurn Company Ltd
R607, Yingzhi Building, 49-3 Suzhoujie Str.
Beijing, China
+86-10 62527842
This email address is being protected from spambots. You need JavaScript enabled to view it.

More Info



清 原 耕 輔   Kosuke Kiyohara
清原光学 営業部   Kiyohara Optics / Sales
This email address is being protected from spambots. You need JavaScript enabled to view it.

Kiyohara Optics Inc.
3-28-10 Funado Itabashi-Ku Tokyo, Japan 174-0041

More Info


Armstrong Optical

+44(0) 1604 654220

This email address is being protected from spambots. You need JavaScript enabled to view it.

More Info