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This Chapter is a little out of order but illuminates a topic we have hinted at in previous Chapters, how does the index of refraction affect the lens conjugates we see when doing centration? The immediate interest came from a call I got because some glass apparently got mixed up in a batch of identical […]

INTRO: INTRODUCTION
Almost all optical elements and systems are sym- metric about their optical axes which means there are only 5 degrees of freedom that will affect op- tical alignment. Likewise, stigmatic images of a point source of light imaged by a finite conjugate optical system have 5 types of symmetry. There is a part of the image that is symmetric about the centroid of the image, and there are 4 symmetries in the plane of the image, namely, even-even, odd-odd, even-odd and odd-even. We show there is a one-to-one correspondence between the im- age symmetries and the degrees of freedom op- tical elements can be moved to align them.

ABSTRACT: There are two basic methods of calibrating a transmission sphere without use of an external artifact, statistical or shear. In the low NA range where shearing is the preferred method, the calibration is difficult to perform precisely because it is hard to measure the shear distance or rotation of the reference surface precisely. If the reference is a Fresnel zone CGH, then there are two centers of curvature that provide an axis that can be located precisely. We show theoretically and experimentally an absolute method of calibrating a TS using one rotational and one translational shear.

ABSTRACT: Talk is largely tutorial by has a two-fold motivation Definitions of kinds of alignmentInitial alignment steps to get light into alignment sensor-autostigmatic microscope, alignment telescope or interferometer Systematic alignment steps using the alignment sensor. Good idea to have a written procedure because many steps Alignment results using real hardware. Robert E. Parks, Benjamin F. […]

Robert E. Parks and William P. KuhnOptical Perspectives Group, LLC, 9181 E. Ocotillo Drive, Tucson, AZ 85749 ABSTRACT We give an example of a Point Source Microscope (PSM) and describe its uses as an aid in the alignment of optical systems including the referencing of optical to mechanical datums. The PSM is a small package […]

From the beginning we have said that centering a lens meant aligning the optical axis of the lens to a reference axis. Up to this point we have assumed the axis was the mechanical axis of a rotary table. Because there are disadvantages to using a rotary table, I was curious to see if there […]