| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optometer capable of measuring the astigmatic axis angle and the power of astigmatism highly precisely regardless of the capacity of judgement of a subject when the optometry is performed by an inexperienced examiner or when there is no examiner. <P>SOLUTION: When "equal (=)" is selected by the subject in a cross cylinder test, 1 is added to a counter (=) for counting the number of times of selecting (=), and it is checked whether the counted value in the counter (=) is 2 or not. If the counted value is 2, the refractive power of cross cylinder lenses 59A and 59B is changed from CC±0.25 D to CC±0.50 D, and a confirmation test is performed to confirm the capacity of judgement of the subject. If the result of the confirmation test is good, the cross cylinder test is continued. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
