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dc.contributor.authorJackson, Larkin Leroyen_US
dc.date.accessioned2015-06-08T19:56:16Z
dc.date.available2015-06-08T19:56:16Z
dc.date.issued1953en_US
dc.date.submitted1953en_US
dc.identifier.otherb14793180en_US
dc.identifier.urihttps://hdl.handle.net/2144/11303
dc.descriptionThesis (M.A.)--Boston Universityen_US
dc.description.abstractThis thesis describes the investigation of Berekt's method of third order lens design as applied to the design of a flat field, photographic triplet. The fields of photographic triplets are usually flattened artificially by adjustment of the astigmatic image surfaces. This process results in degraded image definition in the zonal area of the film plane. The degree of degradation depends primarily upon the original curvature of the Petzval surface with which the astigmatic surfaces are intimately related. If the Petzval surface is steeply curved, then more degradation must be expected than if the Petzval surface is comparatively flat. Most photographic triplets have a Petzval surface whose radius is between two and three times as long as the focal length. The ratio of these radii (called Petzval ratio) chosen for this project was 5.0, which is attained in the final thin lens solution. Use of the Berek basic equations is analyzed in detail. It is shown that with thirteen quantities involved in six equations, it is necessary to account for seven of them either as arbitrarily set values or as dependent variables, "leaving only six true variables for the solution of the basic equations. This accounting is made; and each of the thirteen quantities is identified as an arbitrarily set quantity, a dependent variable, or a true variable. The six basic equations include expressions for focal length, Petzval sum, oblique (lateral) and axial color correction, distortion, and overall lens thickness. The distortion expression is based on the assumption that the diaphragm stop coincides with the second element in the thin lens system. Oblique and lateral color are to be set equal to zero. These two assumptions are justified on the basis of convenience and the lack of any valid method of assigning advantageous residuals. The solution of the basic equations yields individual element powers, spacing, and the number ratio for the first and second elements. [Truncated]en_US
dc.language.isoen_USen_US
dc.publisherBoston Universityen_US
dc.rightsBased on investigation of the BU Libraries' staff, this work is free of known copyright restrictions.en_US
dc.titleAn application of Berek's method to triplet design.en_US
dc.typeThesis/Dissertationen_US
etd.degree.nameMaster of Artsen_US
etd.degree.levelmastersen_US
etd.degree.disciplinePhysicsen_US
etd.degree.grantorBoston Universityen_US


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