RU2089088C1 - Apparatus for investigating vision functions - Google Patents

Abstract

FIELD: ophthalmology. SUBSTANCE: proposed apparatus comprises pre-adaptation chamber accommodating light source, shutter and optical element for observing test objects, shutter and optical element being arranged upstream of pre-adaptation chamber along optical axis of apparatus. Latter further comprises, arranged downstream of pre-adaptation chamber, movable screen made of material having reflection factor equal to that of material of said chamber, mechanism for moving movable screen, set of test objects, light source for illuminating these test objects, set of light filters, and source of interfering light. Besides, apparatus comprises second pre-adaptation chamber, second optical element and shutter arranged, all of them, along second optical axis extending in parallel to first optical axis, shutter being disposed upstream of said second pre-adaptation chamber. Apparatus also comprises second movable screen arranged downstream of said second chamber, commutation unit adapted to switch light source, and two additional optical elements arranged along optical axes extending behind screens in front of test objects. Said interfering light source is arranged between both pre-adaptation chambers, outside of their optical axes and within field of vision of each eye. Said movable screens made of material having reflection factor equal to that of material of both pre-adaptation chambers are rigidly interconnected and have openings to permit observation of test objects and of interfering light source. Said screen moving mechanism is adapted to cooperate with said light source commutating unit and represents handle and, at same time, screen positioning switch. EFFECT: apparatus offers possibility to carry out all-sided study of vision functions. 4 dwg

Description

 The invention relates to the field of medical technology, namely, devices for studying the functions of vision, in particular visual acuity, binocular, stereo vision, phoria, color vision, light and contrast sensitivity, and can be used in a wide network of medical institutions for the diagnosis of eye diseases , in determining professional suitability for a number of specialties, for scientific research.

 A comprehensive assessment of the characteristics of vision is currently an extremely urgent medical task, it is very important for professional selection. There are numerous industries, agriculture, etc. where the assessment of various visible objects is one of the main professional indicators. These include, first of all, the production and operation of visual display devices, cinema, television, the production of dyes, etc. In many cases, the correct assessment of the characteristics of a worker’s vision is associated not only with ensuring the manufacture of high-quality products and their operation, but also with the safety of many of people. These include driving professions, camera and many others.

 In some cases, when studying the functions of vision, it is not enough to evaluate them under constant conditions, it is also necessary to know the range of possible changes in these functions under certain conditions. Thus, in many cases it is necessary to simulate real or most informative conditions for observing various objects.

 A device [1] for the study of audience functions. The device contains two optical axes; lenses that allow to study near and far vision, a set of corrective optics, a device for separating optical axes for independent observation of tests with each eye, two rotating test drums.

 The disadvantage of this device is that the study of visual functions is performed under unchanged observation conditions, the modes of observing adaptation under conditions of interfering illumination, etc. are not studied. This device has a very limited functional diagnostic capabilities.

There is also known a device for studying the functions of vision in changing viewing conditions (selected as a prototype), containing a preliminary adaptation camera with a illuminator located in it, a set of test objects with an illuminator and light filters located outside the adaptation camera, an optical element used to observe the test objects and a dazzler placed at an angle to the camera axis, a screen with a mechanism for moving it, an obturator and a recorder connected to the camera illuminators and a test object, while the screen is installed U test analyzing processes to be moved along the perimeter of the chamber, during the patient study were first closed and screen lit lamp adaptation camera, then the screen is opened and adapt the camera lighting is automatically switched off. Similarly, a study is made of the state of light sensitivity after exposure to the eyes of a blinder. [2]
The disadvantage of this device is the limited ability to study visual functions. In particular, it is not possible to study test objects while observing a bright field and study test objects while simultaneously illuminating the eyes with an interfering light source. In addition, the device only examines visual acuity and light sensitivity; they do not examine such important characteristics of vision as binocular vision, stereo vision, phoria, contrast sensitivity, etc.

 Thus, the aim of the present invention is to improve the accuracy of diagnosis of the state of visual functions of a person, by expanding the modes of study of the characteristics of vision.

 This goal is achieved by the fact that the device for the study of vision functions, comprising a pre-adaptation camera with a illuminator located in it, an obturator installed in front of the camera on the optical axis and an optical element for observing test objects located behind the pre-adaptation camera, a movable screen made of material with reflection coefficient equal to the reflection coefficient of the camera material, with a mechanism for its movement, a set of test objects with a illuminator, a set of light filters, as well as a source IR of interfering light, equipped with a second pre-adaptation camera mounted on the second optical axis parallel to the first optical axis, a second optical element and a shutter mounted in front of the pre-adaptation camera, a second movable screen located behind the camera, as well as a light source switching unit and two additional optical elements located on the optical axes behind the screens in front of the test objects, while the interfering light source is located between the cameras th adaptation is their optical axes and the field of view of each eye; movable screens made of material with a reflection coefficient equal to the reflection coefficient of the material of the preliminary adaptation cameras are rigidly interconnected and have openings for observing test objects and a lamp of interfering light, and the screen moving mechanism interacts with the light source switching unit, made in the form of a handle and screen position switch.

 In FIG. 1 shows a General view of the device; in FIG. 2 is a conventional scan of the screens, in FIG. 3 is an electrical diagram of the device, in FIG. 4-a - the mechanical part of the switching unit of the light source 17 (without a stand-alone camera switch preliminary adaptation), Fig 4-b options for the implementation of the switch position of the movable screens.

 A device for studying the functions of vision contains two optical axes on each of which pre-adaptation cameras 1 (1 'for the second optical axis, respectively), an obturator 2 (2'), an optical element 3 (3 ') are placed in front of the camera inlet. A movable screen 4 (4 '), a second optical element 5 (5'), a set of test objects 6 (6 '), a set of light filters 7 (7') and a common illuminator 8 located behind the camera for two optical axes. Screens 4 and 4 'are rigidly interconnected and made of material with a reflection coefficient equal to the reflection coefficient of cameras 1 and 1'. The device also contains a illuminator 9 cameras pre-adaptation. 1 and 1 ', located outside the field of view of the patient, so that cameras can be illuminated, for example, above the cameras in the device body; a source of interfering light 10 located between the preliminary adaptation cameras 1 and 1 'outside their optical axes, in the field of view of the patient. Pre-adaptation cameras have openings 11 (11 ') for observing test objects; openings 12 (12 ') for observing the source of interfering light and 13 (13') for the passage of light from the illuminator 9 into the preliminary adaptation chambers 1 and 1 '. Accordingly, the movable screens 4 and 4 'have openings 14 (14') for observing test objects: openings 15 (15 ') and 16 (16') for observing test objects when exposed to an interfering light source 10.

 The device has a switching unit 17 of light sources 8, 9, 10. The switching unit is connected to the power supply 18 (see Fig. 3) and contains three mechanical switches 19, 20, 21, switching power supply circuits of the lamps 9, 10, 8, respectively. The switching unit 17 contains a stand-alone switch 22 illuminator cameras 1 and 1 'pre-adaptation.

 The movable screens 4 and 4 'have a movement mechanism made in the form of a handle 23 and screen position switches 24 (Fig. 4). The switch 24 is designed to fix the holes 14 (14 '), 15 (15'), 16 (16 ') in the desired (working) position relative to the main optical axes. The switch 24 can be performed, for example, using mechanical ball retainers 26 (Fig. 4B). The screen moving mechanism interacts with the switching unit 17 by mechanically closing and opening the switches 19, 20, 21 when the handle 23 is rotated. The interaction can be organized by means of a rotating cam 27 combined with the axis of the screen position switch FIG. 4a.

 If necessary, the device can be equipped with a time recorder (25), a distance regulator between the optical axes of the first optical elements, etc. (not shown in damn).

 The device operates as follows.

 When examining far vision, the patient looks through the optical elements 3 3 'into the preliminary adaptation cameras 1 and 1'.

There are three main modes of operation of the device:
a) manual 23 and the switch 24 moves the screens 4 and 4 'to position A (see Fig. 2) in which the holes of the chambers 1, 1' of preliminary adaptation 11; eleven';12; 12 'is closed by screens, at the same time, the switching unit 17 is activated (see Fig. 3, 4), while the illuminator 9 of the cameras 1 and 1' is turned on and the patient sees in front of him only the illuminated cameras of preliminary adaptation.

 b) the handle 23 and the switch 24 move the screens 4 and 4 'to position B (Fig. 2) in which the openings of the chambers 11 and 11' are open and the patient observes through the openings of the screens 14 and 14 'through the optical elements 5 and 5', respectively, the sets tests (6 and 6 ', which may vary depending on the nature of the study). At the same time, the switching unit 17 (see Fig. 3, 4) is activated, and the illuminator 8 is turned on and the patient observes the selected tests 6 and 6 ', the brightness of which is regulated by a set of filters 7 and 7'.

 c) in the third mode, the handle 23 and the switch 24 move the screens 4 and 4 'to position B (Fig. 2), in which the openings of the chambers 11 and 11'; 12 and 12 'are open and the patient through the openings 15 and 15' observes through the optical elements 5 and 5 ', respectively, test sets 6 and 6' under the interfering effect of the interfering light source 10, which through the openings 16 and 16 'of the screens 4, 4' and through holes in the chambers 12, 12 'affects the patient's eyes. Simultaneously with moving the screen to position B, the switching unit 17 is activated (Fig. 3, 4), and the illuminator 8 and the interfering light source 10 are turned on, so the patient observes the selected tests 6 and 6 ', the brightness of which is regulated by a set of filters 7 and 7' with interfering exposure to the source 10.

 In the study of near vision, the elements 3 and 3 'are removed from the field of view of the patients. The remaining operations are carried out similarly to the modes of research of distant vision.

 The self-contained switch 22 (Fig. 3) of the illuminator of the preliminary adaptation chamber allows carrying out the studies described above with illuminated preliminary adaptation cameras. In this case, regardless of the position of the switch 24 and the switch 19, the illuminator of the preliminary adaptation chamber 9 is turned on.

 The developed device design, due to the presence of two independent optical axes, makes it possible, compared with the prototype, to check such vision parameters as stereo vision, binocular vision, and phoria. And also thanks to the presence of an autonomous switch and a light source switching unit, it allows to additionally study the characteristics of vision in the following modes (in the prototype these modes are impossible).

 A. Testing visual acuity, contrast sensitivity.

α)) on a dark object in a bright background (for distance and near)
β)) on a dark object, with interfering illumination (for distance and near)
γ)) of points A (α and β) for different brightness of objects (test) B.

 B. Verification of binocular, stereo vision, phoria.

α)) with an object (test) on a bright background
β)) with an object (test) with interfering illumination
γ)) of points B (α and β) at different brightness of the test.

 C. Verification of color sensation.

α)) with an object on a bright background
β)) with an object with interfering illumination
γ)) of points C (α and β) at different brightness of the test.

 D. Study of the restoration and change of vision functions for points A, B, C.

 The device in comparison with known analogues has an expanded range of tested characteristics of vision, which significantly improves the quality of diagnosis.

 So, for example, traditionally in devices of this type, a table with signs located in the room is imitated. In the room, observation in the dark is justified, since in this case similar observation conditions can be formed. Another characteristic of vision, in which signs are observed on a bright background, is also really important. This information can provide additional information on professional suitability and give recommendations, for example, on darkening glasses in people with increased sensitivity to light, etc.

 In addition, it is known that preliminary adaptation to light also changes the characteristics of vision. Thus, adaptation to white reduces the difference between blue colors compared to dark adaptation, and a decrease in brightness by one logarithmic unit leads to an increase in the differences between these colors. In the field of green colors, on the contrary, adaptation to white increases the differences between stimuli compared to dark adaptation, and a decrease in brightness “compresses” colors in space, i.e. color discrimination worsens. There are many other characteristics of vision that change under different conditions of adaptation (E. Sokolov and others. Color vision. Pp. 92, 94 and others).

 Thus, the advantage of the developed device is the ability to study the characteristics of vision in various variable test conditions.

 AO "Impulse" made a prototype device for studying the function of vision in accordance with the stated technical solution. Tests have confirmed the high efficiency and information content of the studies.

 The developed new device provides an opportunity, in comparison with the prototype (Niktoskop 01 Device, development of VNIIP), to study at least 3 more visual functions (stereo vision, binocular vision, phoria). In this case, the characteristics of vision can be studied in at least 10 additional test modes (see sheet 6 of the description), which allows honey. personnel dramatically improve the accuracy of diagnosis and objective assessment of the state of vision. In addition, the device under development is the first domestic device to assess complex-specific vision parameters necessary for the selection of relevant specialists in a number of professions.

Claims (1)

 A device for studying the functions of vision, comprising a pre-adaptation camera with a illuminator located in it, an obturator installed in front of the camera on the optical axis and an optical element for observing test objects located behind the preliminary adaptation camera, a movable screen made of material with a reflection coefficient equal to the reflection coefficient camera material, with a mechanism for moving it, a set of test objects with a illuminator, a set of light filters, as well as a source of interfering light, characterized in that the device is equipped with a second pre-adaptation camera, a second optical element and a shutter mounted on the second optical axis parallel to the first optical axis, mounted in front of the pre-adaptation camera, a second movable screen located behind the camera, as well as a light source switching unit and two additional optical elements, located on the optical axes behind the screens in front of the test objects, while the source of interfering light is located between the cameras preliminary adaptation outside their optical axes in the field of view of each gas, movable screens made of material with a reflection coefficient equal to the reflection coefficient of the material of the preliminary adaptation chambers are rigidly interconnected and have openings for observing test objects and a lamp of interfering light, and the screen movement mechanism interacting with the light source switching unit, is a handle and a screen position switch.

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