54 results about "Visual acuity chart" patented technology

Eye chart for testing visual acuity which includes a plurality of optotypes arranged in a plurality of lines with each optotype in a line having a uniform resolution throughout and the resolution for each optotype in a given line is the same. The optotypes are generated by standardizing the maximum resolution angle any one letter may have and such is done by utilization of a design circle which represents the maximum resolution.

Disclosed herein are system and method for testing and analysis of visual acuity and changes using an acuity model, the acuity model generated based on one or more acuity chart design parameters and candidate acuity parameters calculated using the acuity test data of the subject, the acuity model comprising a chart-specific psychometric function determined using a family of multiple-optotype psychometric functions, and wherein the acuity model is configurable to estimate possibility of obtaining the acuity test data of the subject.

The invention discloses a visual acuity chart device, a vision self-testing system and a self-testing method. The visual acuity chart device, the vision self-testing system and the self-testing method solve the problems that the existing physical examination or vision check is completed only under the assistance by workers or medical staff, the self check cannot be performed, and the change of vision diminution cannot be timely found when a student studies in a classroom for a long time. The visual acuity chart device, the vision self-testing system and the self-testing method are technically characterized in that by utilizing the brightness compensation automatic control on a backlight source, the accuracy and reality of vision testing are improved, the vision change of the student can be known by a school, parents and the student self, and the effects of early finding, early prevention and early treatment are realized.

Disclosed herein are system and method for testing and analysis of visual acuity and changes using an acuity model, the acuity model generated based on one or more acuity chart design parameters and candidate acuity parameters calculated using the acuity test data of the subject, the acuity model comprising a chart-specific psychometric function determined using a family of multiple-optotype psychometric functions, and wherein the acuity model is configurable to estimate possibility of obtaining the acuity test data of the subject.

The invention discloses a vision detection method, device, electronic equipment and computer storage medium. The method includes measuring the test distance between the subject and the vision chart box; The display size of the visual acuity chart; through the adjusted visual acuity chart, the visual acuity test is performed on the subject to obtain the visual acuity value of the subject. Through the above method, the visual acuity detection process is not affected by the venue, even when the venue does not meet the standard distance, the visual acuity can still be accurately detected, which is very convenient.

The invention discloses a multifunctional detection visual acuity chart which comprises a rectangular plate body, wherein plugging slots are formed in the rectangular plate body; a black plugboard and a red plugboard are respectively plugged into the plugging slots; the front end surface of the rectangular plate body is coated with a green coating layer; a plurality of circular grooves are formed in the green coating layer; circular turntables are connected into the circular grooves in a plugging manner; E-shaped grooves are formed in the circular turntables; the E-shaped grooves are communicated with the adjacent plugging slots in the rectangular plate body; four positioning slots are formed in the upper, lower, left and right side walls of each circular turntable; the connecting line of two positioning slots at opposite positions is a horizontal line or a vertical line; four positioning ball-head plungers corresponding to the positioning slots are screwed into the inner side walls of the circular grooves; ball heads of the positioning ball-head plungers are embedded into the corresponding positioning slots; arc-shaped shifting handles are formed on the circumferential edges of the surfaces of the circular turntables; the shifting handles are positioned between the adjacent positioning slots. The multifunctional detection visual acuity chart can simultaneously detect red-green color-blindness, and the direction of E can be changed to prevent cheating.

The invention discloses a visual chart which is characterized in that positions of visual chart symbols of the same visual value on the visual chart are interchangeable. According to the visual chart, through manual or circuit exchange, free adjustment of the visual chart symbols of the same visual value on the visual chart is achieved, and the problem that in the prior art, recitation of the visual chart cannot be coped with is solved.