Visual chart suitable for clinical test and use method thereof

Abstract

The invention discloses a visual chart suitable for a clinical test and a use method of the visual chart. The optotype size, the geometric increase rate, the line number, the optotype spacing and the line spacing of the visual chart all adopt international standards, and the innovation point is that each row of optotypes of an optometry chart (chart R) is composed of a C optotype with a gap and four rolling E optotypes. Each of the two optotypes has upward, downward, leftward and rightward orientations. The standardized operation specifications of the ETDRS visual chart and ETDRS optometry are gold standards of international clinical drug trials. On the basis of the rolling E optotypes commonly used by Chinese people, the combination of the two optotypes is provided in the newly designed optometry chart, namely, one C optotype exists in each row of rolling E optotypes, so that the requirements of identification and expression habits of Chinese people are better met during use, meanwhile, qualitative and quantitative measurement and verification of the axial direction and the degree of astigmatism of a subject can be performed, and the vision detection efficiency and accuracy can be improved.

Description

technical field [0001] The invention relates to an eye chart suitable for clinical trials and a using method thereof. Background technique [0002] The classic ETDRS table was born in 1982 and consists of three independent alphabetic vision tables, including the optometry table (Table R), the right eye table (Table 1) and the left eye table (Table 2). At that time, the National Eye Institute (NEI) of the United States urgently needed a set of standardized visual acuity charts to conduct a large-scale "Early Treatment of Diabetic Retinopathy Study" (ETDRS). Dr. Rick Ferris integrated Bailey-Loivre's logarithmic vision chart with 5 letters per row and Sloan's 10 Latin letters into a new set of vision charts. The inspection distance is 4 meters. The vision chart has been approved by the National Eye Institute of the United States and the FDA of the United States for "Early Treatment of Diabetic Retinopathy Research", so it is named ETDRS Vision Chart. , letter spacing, and li...

AI Technical Summary

Problems solved by technology

During the implementation process, for some middle-aged and elderly subjects, even if they can clearly identify the letter optotype (seeing) during the vision test, they may fail because they cannot accurately describe the recognized letter optotype (reading) Misunderstood situations will seriously affect the efficiency of vision detection and may lead to large deviations in detection results

[0005] At present, there are ETDRS tables on the market that use rolling E as the visual standard. For Chinese people, especially middle-aged and elderly people, they have better recognition and expression effects. However, due to the lack of a circular visual standard, they cannot fully meet the standard optometry specifications. Qualitative and quantitative measurement and verification of the axial direction of astigmatism and the degree of astigmatism

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