RU78665U1 - DEVICE FOR DETERMINING VISION PARAMETERS - Google Patents

Abstract

The utility model relates to the field of ophthalmology. Effect: improving the accuracy of assessing color perception and visual acuity, including in twilight conditions. The technical result is achieved by the fact that in the device for determining the parameters of vision, containing a display, a generator of test objects and a control device, the second output of the control device connected to the first input of the generator of test objects, a block for setting image parameters is introduced, the first information input of which is connected to the output of the generator of test objects, the output is connected to the input of the display, and the second control input of this unit is connected to the first output of the control device, and setting parameters from mapping performed with simultaneous or sequential changes in the size, shape, orientation, color and color saturation, and the test object and background images.

Description

The utility model relates to the field of ophthalmology and can be used to measure vision parameters.

A device for the study of color perception, made in the form of tables printed by the printing method (Rabkin EB, Polychromatic tables for the study of color perception / - 11th ed., Revised. - Mn .: Yu.M. Sapozhkov, 2005. - 44 from.). The device contains images of test objects made in the form of round or oval optotypes of various colors and their saturation. However, the described device has significant drawbacks: the presence of numbered tables with the image of strictly defined test objects with predetermined strictly defined color shades makes it possible for the patient to guess the correct answers. The accuracy of determining the parameters of color vision is limited to a strictly defined set of color shades. The device does not allow the assessment of color perception and visual acuity in twilight conditions.

A device for studying color perception, made in the form of a display test, (Clinical Physiology of Vision: Essays / Ed. AM Shamshinova - M .: T.M. Andreeva, 2006, p. 313), is freely available on the Internet at: http://colorvisiontesting.com/. During testing, test objects are displayed on the computer screen, most of which are similar to those in polychromatic tables. The test subject is asked to determine what he sees on the screen and compare with the correct answer. In fact, the images of tables made by the printing method are simply transferred to the computer screen. The disadvantages of such a device are:

- the complexity of the application in medical practice, because Requires a computer connected to the Internet via a high-speed connection;

- the presence of only strictly defined sets of test objects with predetermined strictly defined color shades, which makes it possible for the patient to guess the correct answers;

- limiting the accuracy of determining the parameters of color vision with a strictly defined set of color shades;

- the device does not allow the assessment of color perception and visual acuity in twilight conditions.

Closest to the claimed device is a device for checking visual acuity according to the patent of the Russian Federation for utility model No. 73186,

comprising a test object generator, a display, an image magnification device, and a control device. When the device is operating, the patient is presented with optotypes of various sizes and orientations, and the size of the optotypes is continuously adjustable in a large dynamic range.

The disadvantages of such a device are:

- the impossibility of assessing color perception and visual acuity in twilight conditions;

- the impossibility of determining the parameters of color vision.

Effect: increasing the accuracy of evaluating color acceptance and visual acuity, including in twilight conditions.

The technical result is achieved by the fact that in the device for checking visual acuity (RF patent for utility model No. 73186) containing a test object generator, a display and a control device, the second output of the control device being connected to the first input of the test object generator, an establishment unit is introduced image parameters, allowing in a controlled manner simultaneously or sequentially change the size, shape, orientation, color and color saturation of test objects and image background, the first information input of the block setting the image parameters is connected to the output of the test object generator, the output of the block is connected to the input of the display, and the second control input of this block is connected to the first output of the control device.

The proposed device is illustrated by drawings of figures 1-8:

Figure 1 - block diagram of the device

Figure 2 - view of several test objects

Figure 3 - change the geometric shape of the test object

Figure 4 - change the color of the test object.

Figure 5 - change in color saturation of the test object.

6 is a change in the orientation of the test object.

Fig.7 - change the background color of the image.

Fig - change the color saturation of the background image.

Fig.9 - change in color saturation of the set of test objects.

The device for determining the parameters of vision (Figure 1), contains a display 1, the input of which is connected to the output of the device for setting the image parameters 2. The first information input of the device for setting the image parameters 2 is connected to the output of the test object generator 3. The second control input of the device 2 is connected to the output of the control device 4. The second output of the control device 4 is connected to the first input of the generator of test objects 3. The display can also be made in the form of a reflective screen.

The test object is made in the form of at least one closed planar curvilinear figure. It is possible to perform a test object in the form of several figures (Figure 2). The device for setting the image parameters (Figure 1, position 2) allows you to simultaneously or sequentially change the geometric shape (Figure 3), color (Figure 4), color saturation (Figure 5), orientation (Figure 6) of the test object , as well as change the color (Fig.7) and the color saturation of the background image (Fig.8).

The proposed device operates as follows. The generator of test objects 3 through the block setting the parameters of the image 2 transmits images of test objects and background to the display I. The control device 4 acts on the block setting the parameters of the image 2 through its control input. The numerical values of this effect are linearly and unambiguously associated with the characteristics of the image and background and have sufficient discreteness. The control device 4 through its second output controls the operating mode of the generator of test objects 3.

The image parameter setting unit (Fig. 1, pos. 2) is a special regulatory electronic or optical device (the specific principle of operation is not fundamental). At the same time, the main characteristic of the image parameter setting unit (Fig. 1, item 2) is the dynamic range of parameters of test objects and the background image, which is set at least 256 (the standard of the simplest display). The image parameter setting block (FIG. 1, pos. 2) has calibration scales or other means of determining and fixing the values of the set parameters of test objects and the background image.

Work with the device as follows.

One or more test objects of various shapes, colors and color saturations are presented to the patient sequentially with simultaneous variation in size, while fixing the numerical parameters characterizing the images of test objects and the background image. The numerical parameters of the minimum test object stably distinguishable by the patient are digital characteristics of visual acuity. The patient’s perception stability is checked by replacing the test object with a similar one in size, changing its geometric shape or its orientation in the display plane. Such changes are used by the doctor to establish the true parameters of the patient’s vision and to prevent incorrect testimony in order to overestimate the parameters of vision.

The measurement of vision in twilight conditions is as follows.

The device and patient are placed in a dark room. Twilight and night vision is checked with an inverted image of a test object (light against a dark background). Pre-change the background color to dark or completely black. In this case, the test object will appear bright. Then, in the same order, the patient is tested and the numerical values of the minimum test object stably distinguishable by the patient are recorded. The numerical parameters of the minimum guest-object stably distinguishable by the patient are digital characteristics of visual acuity in twilight and night conditions.

Assessment of color perception using the proposed device is as follows.

The patient is presented with an image consisting of a set of multi-colored test objects. At the same time, the background color is set different from all the colors of the test objects. Test objects of certain colors are added to a geometric shape or a typical image (letter, number, etc.). Adjust (decrease) the color saturation at the same time of all test objects from the maximum - downward until the patient no longer steadily sees the figure represented by the test objects. The change in color saturation of the set of test objects is illustrated by the images in Fig.9. Stability of perception is checked by substituting or changing the orientation of the figure that the test objects make up. The number characterizing the color saturation at the moment when the patient ceases to steadily distinguish the figure formed by the test objects is a characteristic of the color perception threshold.

Using the proposed device can improve the accuracy of the assessment of color perception and visual acuity, including in twilight conditions.

Conducting such studies with increased accuracy is very important in the training of specialists with professional vision (military personnel, sailors, pilots, transporters, etc.) and in the early diagnosis of some ophthalmic diseases. For example, when testing to distinguish between yellow and blue light, early signs of glaucoma can be detected (Clinical Physiology of Vision: Essays / Edited by A.M. Shamshinova - M .: T.M. Andreeva, 2006, pp. 323, 350).

Claims (1)

A device for determining vision parameters, comprising a display, a test object generator and a control device, the second output of the control device being connected to the first input of the test object generator, characterized in that an image parameter setting unit is introduced into the device, the first information input of which is connected to the output generator of test objects, the output is connected to the input of the display, and the second control input of this unit is connected to the first output of the control device, and the establishment of image parameters roizvoditsya with simultaneous or sequential changes in the size, shape, orientation, color and color saturation of test objects and the background image.