环形散光表的设计及应用

The design for the ring astig matic chart and its application

依据我们所得出的屈光不正与模糊视力的关系式,L=log(1.16738 基础视力)log(58.84+k/58.84-k)-logp-logk+5,设计并制作出环形散光表及瞳孔值校正尺。对需要验光配镜的屈光不正眼诊断后,先测量其瞳孔直径,然后再看环形散光表,记录其所见模糊区的形状及二条主要径线上的最小可辨模糊环,再查瞳孔值校正尺,便能得出一个较为可靠的镜片类型及屈光不正度。经临床试用表明,用本法所测结果与实际配镜处方相比,其符合率为76～95%,其准确性稍优于日本TOPCON公司出产的RM-200B型电脑验光仪的检查结果,稍低于散瞳检影验光的结果。但本法简化了屈光不正眼的配镜工作,提高了工作效率,可供临床验光配镜时使用。

We have got an equation about the relation between ametropic and blurring visual acuity ( unaided vision): L = Log ( 1.16738 original visualacuity of logarithmic system, P= pupil diameter, K=ametropic dioptre). According the equation, we have designed and made out the Ring Astri-gmatism Chart and the Ruler of checking pupil diameter value.First , we should measure the pupil diameter of the patient with refractive errors, then ask the patient to look at the Ring Astigmatism Chart and record the minimal ring at two major meridans distinguished by the patient. Following these prccesses, we can use the Ruler of checking pupil diameter value to make sure of the type and dioptre of glasses. Through clinical practice and the comparison of obove-mentioned applied result with the method of matching glasses, it has been attained that the conformable rate is 76-95% . The use of the Ring Astigmatism Chart is simple , convenient and easy. It can be applied in clinic.