| 摘要 |
An eyesight tester for possibly finding short-sightedness, long-sightedness etc. In the apparatus are included a number of lenses (34, 34a), differing with respect to lens power, embedded in at least one rotationally arranged wheel (24, 26) and located and distributed along an imaginary circle passing through an ocular (36, 38). The power value (for example -3) of each lens (f or example 34a) is indicated on the side surface of the respective wheel (24) i n such positions relative to the associated lens (34, 34a) that the power valu e (-3) of each single lens (for example 34a) will appear in a visible position (40, 41) when the associated lens (34a) is in the ocular (36, 38).
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