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Phase Contrast Test Slide

H.S.E Test Slide

This is a photograph of the H.S.E./NPL Phase Contrast Test Slide

Macro Photograph


The Phase Contrast Test Slide is manufactured to test the sensitivity of a phase contrast microscope to a given shift in phase between the direct ray and the diffracted ray paths for a specific configuration of the microscope. This slide is designed to test sensitivity to phase and not the resolution limit or limit of visibility for the microscope.

Significance in the Environment:

Characteristic Features:

The patern on this slide consists of seven bands of twenty lines each. The width of the individual lines range from 1.1 micrometer for the first set to 0.25 micrometers for the seventh set of lines. The depth of each engraved line from which the resin cast is made is approximately one tenth of the line width. The refractive index of the resin used to make the cast is 1.58.

Associated Particles:


LeGuen, J.M.M., T.L. Ogden, T. Shenton-Taylor and J.F. Verrill, The HSE/NPL phase-contrast test slide", Ann. Occup. Hyg., Vol. 28, no. 2, pp. 237-247, 1984 This reference briefly gives some of the specifics on the design of the test slide.