Recent content by Mr_Chen

  1. M

    Undergrad Type of image from an afocal optical system

    An image from afocal system always is real. 2 types afocal; Keppler with 2 positive lens and Lagruerre with 1 positive len + 1 negative len, but f of positive always > f of negative.
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    Undergrad Difference between intensity and power

    Intensity is power per area ?