Collimating eyepiece


  • Webster's Revised Unabridged Dictionary
    • Collimating eyepiece an eyepiece with a diagonal reflector for illumination, used to determine the error of collimation in a transit instrument by observing the image of a cross wire reflected from mercury, and comparing its position in the field with that of the same wire seen directly.
    • Collimating eyepiece See under Collimate.
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