While often overlooked in favor of vision systems and other high tech devices (which we can also help with), the optical comparator is still a very cost effective, capable piece of equipment with many applications. Dorsey's machines are built to last and will more than likely outlive most people's careers. Give us a call and we would be happy to schedule a demo for you to see how they can benefit your organization's measurement program.
The optical comparator is a non contact inspection instrument that applies the principle of optics to magnify and project the image of an inspected part. A light source emits light beam that travels through prism and projects the shadow of an object onto a screen a few feet away so it can be compared with a chart showing tolerance levels for the part. Many optical comparators also include surface illumination, which will also allow features on the surface to be measured. For example, you could measure the size of Abe Lincoln's head on a penny by viewing the surface of the penny with surface illumination.
Screen sizes: Various optical comparators screen sizes are available from 14" to 80". When selecting optical comparator screen size, it is important to determine how much of the part must be viewed at one time.
Lenses: Lenses are available in magnification ranging from 10X to 100X. Smaller magnification allows you to view more of the part at one time, but larger magnification will provide more accuracy.
Readouts: Readouts are available in a basic dimensional display of the stage position up to units that calculate geometric functions (circle, radius, location, angle, etc.).
Edge Detection: Dorsey comparators use internal edge detection, which allows the readout to "see" the edge without the unsightly optical probes on the outside of the screen which hide the actual measured edge.
Overlays: Charts can be clipped to the display to compare a part to a known shape and size for a fast and easy way to evaluate parts for conformity to a standard dimension of shape.
Stages: Stages are available in many sizes with a broad range or travel and with helical movement (which rotates the stage for checking thread patterns). They can be moved manually or be motorized. Motorized stages coupled with a programmable display can be used as fully CNC visual inspection machines.
Fixtures: Many fixtures are available for supporting parts on the stage for measurement. Centers and V-blocks can be used for holding shafts. Clamps, rotating bases, glass plates, and other fixtures can all be used for holding workpieces to allow many possibilities for measurement of even the most difficult to fixture parts.
Call us today for more information on the full line of Dorsey Optical Comparators, as well as other Dorsey products!!