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PubMed · 2765127

Alignment modification for pencil eye shields.

M D Evans·M Pla·E B Podgorsak
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Abstract

Accurate alignment of pencil beam eye shields to protect the lens of the eye may be made easier by means of a simple modification of existing apparatus. This involves drilling a small hole through the centre of the shield to isolate the rayline directed to the lens and fabricating a suitable plug for this hole.

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M D Evans, M Pla, E B Podgorsak. 1989. Alignment modification for pencil eye shields.. https://doi.org/10.1016/0958-3947(89)90178-7

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