WY21A Interference Fringe Visuometer, based on Thomas Young's interference theory, uses grating to produce interference lamp-house. This compact, flexible machine could be applied to measure interference fringe visual acuity. Its clinical tryout shows that WY21A is suited for daily practice as it is able to give a fast, easy and reliable preoperative assessments and prediction of visual recovery for most age-related cataract patients.
Equipment Design ; Humans ; Optometry ; instrumentation ; methods

An instrument for subjective measurement of tonic accommodation has been established based on the Badal system and Scheiner principle. The results of tonic accommodation between subjective measurement and objective measurement have no significant difference. Its establishment is important for the measurement of accommodation parameter in the myopia research center.
Accommodation, Ocular ; physiology ; Diagnostic Techniques, Ophthalmological ; instrumentation ; Humans ; Optometry ; instrumentation ; methods ; Refractometry ; instrumentation ; methods ; Visual Acuity

OBJECTIVE: To compare the results of the three methods of Suresight handheld autorefractor, table-mounted autorefractor and retinoscopy in examination of juveniles patients with or without cycloplegia.
 METHODS: Firstly, 156 eyes of 78 juveniles (5 to 17 years old) were examined by using WelchAllyn Suresight handheld autorefractor and NIDEK ARK-510A table-mounted autorefractor with or without cycloplegia; secondly, retinoscopy was performed with cycloplegia.
 RESULTS: The spherical power measured by methods without cycloplegia were significantly greater than those measured with cycloplegia (P<0.05); without cycloplegia, there was no significant difference in spherical power, cylindrical power and cylindrical axis between Suresight handheld autorefractor and retinoscopy (P>0.05). These results were highly consistent, suggesting a tendency towards a short sight. However, the spherical power and cylindrical power measured by table-mounted autorefractor was significantly different (P<0.05); with cycloplegia, there was significant difference in spherical power between Suresight handheld autorefractor and retinoscopy (P<0.05).
 CONCLUSION Cycloplegic retinoscopy is necessary for juvenile refraction examination. Under natural pupil situation, Suresight handheld autorefractor is better than table-mounted autorefractor, though both show a myopia tendency. Nevertheless, table-mounted autorefractor can be taken as a recommendation for the prescription of lens trial. As a strong reference for subjective optometry, retinoscopy should be the gold standard for measuring refractive errors.
Adolescent ; Child ; Child, Preschool ; Humans ; Myopia ; diagnosis ; Optometry ; instrumentation ; methods ; Refraction, Ocular ; Refractive Errors ; Retinoscopy

A vernier optometer, based on the Scheiner principle, that makes use of polarized light, is designed and developed. It is specialized in measurement of tonic accommodation, accommodation and accommodation response. The vernier optometer has been proved by chinical testing results, to be a reliable and effective instrument with fine stabilily, good repeatability and sensitivity for short sight study relating to oculogyral parameters.
Accommodation, Ocular ; Adult ; Diagnostic Techniques, Ophthalmological ; instrumentation ; Equipment Design ; Humans ; Myopia ; diagnosis ; Optometry ; instrumentation ; Refraction, Ocular ; Reproducibility of Results ; Visual Acuity

In this paper, it was studied how physics affected development of optometry in the United States, from aspects of formation and academization of optometry. It was also revealed that history of optometry was analogous to history of engineering. Optics in the 19th century was divided into electromagnetic study of light and visual optics. Development of the visual optics promoted professionalization of ophthalmology that had already started in the 18th century. The visual optics also stimulated formation of optometry and optometrists body in the late 19th century of the United States. The American optometrists body were originated from opticians who had studied visual optics. Publication of several English academic textbooks on visual optics induced appearance of educated opticians (and jewelers). They acquired a right to do the eye examination in the early 20th century after C. F. Prentice's trial in 1897, evolving into optometrists. The opticians could be considered as craftsmen, and they were divided into (dispensing) opticians and optometrists. Such history of American optometrists body is analogous to that of engineers body in the viewpoints of craftsmen origin and separation from craftsmen. Engineers were also originated from educated craftsmen, but were separated from craftsmen when engineering was built up. Education system and academization of optometry was strongly influenced by physics, too. When college education of optometry started at American universities, it was not belonged to medical school but to physics department. Physics and optics were of great importance in curriculum, and early faculty members were mostly physicists. Optometry was academized in the 1920s by the college education, standardization of curriculum, and formation of the American Academy of Optometry. This is also analogous to history of engineering, which was academized by natural sciences, especially by mathematics and physics. The reason why optometry was academized not by medicine but by physics is because ophthalmologists did not have conciliatory attitudes to optometry education. Optometry became independent of physics from the 1930s to the 1940s. Optometric researches concentrated on binocular vision that is not included to discipline of physics, and faculty members who majored in optometry increased, so that optometry departments and graduate schools were established around 1940. Such independence from natural sciences after academization also resembles history of engineering. On the contrary, history of optometry was different from history of ophthalmology in several aspects. Ophthalmology had already been formed in the 18th century before development of visual optics, and was not academized by visual optics. Ophthalmologists body were not originated from craftsmen, and were not separated from craftsmen. History of optometry in the United States from the late 19th to the mid 20th century is analogous to history of engineering rather than history of medicine, though optometry is a medical discipline.
History, 19th Century ; History, 20th Century ; Humans ; Ophthalmology/history ; Optics and Photonics/history ; Optometry/*history ; Physics/*history ; United States

INTRODUCTIONDuring cataract surgery under regional (retrobulbar, peribulbar or sub- Tenon's) or topical anaesthesia, many patients experience a variety of visual sensations in their operated eye intraoperatively. Between 3% and 16.2% of patients are frightened by their intraoperative visual experiences, which may increase the risk of intraoperative complications and affect patients' satisfaction with the surgery. This study aims to determine optometry students' beliefs and knowledge of visual sensations experienced by patients during cataract surgery under regional and topical anaesthesia.

MATERIALS AND METHODSA nationwide survey of all Malaysian optometry students using a standardised, self-administered questionnaire.

RESULTSAll 129 optometry students participated in the survey, giving a 100% response rate. Overall, 26.4% and 29.5% of the students believed that patients undergoing cataract surgery under regional and topical anaesthesia, respectively, may experience no light perception, while 78.3% and 72.9%, respectively, thought that patients would experience light perception. Many respondents also believed that patients might experience a variety of other visual sensations. Of all respondents, 70.5% and 74.4% of students believed that patients undergoing cataract surgery under regional and topical anaesthesia, respectively, may be frightened by their visual experience and 93.0% and 85.3%, respectively, felt that preoperative counselling might help to alleviate this fear.

CONCLUSIONMany optometry students are aware that patients might encounter a variety of visual sensations during cataract surgery under local anaesthesia. A high proportion of students believe that patients may experience fear as a result of the intraoperative visual sensations and felt that preoperative counselling would be helpful.

Adult ; Anesthesia, Conduction ; Cataract Extraction ; psychology ; Counseling ; Fear ; Female ; Humans ; Intraoperative Period ; Malaysia ; Male ; Optometry ; education ; Sensation ; Visual Perception

The optometry in physical examinations is conducted manually at present and this method is neither precise nor efficient. After studying the standard logarithmic visual acuity charts which is popular in our country, we have designed an optometry system based on Client/Server Computing Mode. The system's architecture and its working principle are also presented in the article.
Algorithms ; Artificial Intelligence ; Computer Simulation ; Equipment Design ; Humans ; Information Storage and Retrieval ; methods ; Microcomputers ; Optometry ; instrumentation ; methods ; Physical Examination ; instrumentation ; methods ; Software Design