RU2439638C2 - Screen - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: optical and/or technical screen with a concave form of the curvature radius, is made such that one or more of its surfaces visible to an observer has a concave form with curvature radius R more than twice greater than distance from the screen L to the observer and not more than double the distance to the nearest source, the glare of which needs to be eliminated.

EFFECT: reduction or attenuation of glares from the screen which can be seen by an observer.

2 cl

Description

The invention relates to the field of ergonomics, and in particular to designs of optical screens, including displays, projection screens, other carriers of dynamic and static images, as well as technical screens designed to protect people and / or technical devices from harmful effects.

Well-known means of displaying graphic (static and / or dynamic) information containing a surface on which a static, variable or dynamic image is formed - optical screens. Protective screens and screens installed between the observer and the surface on which the image is formed are also well known: transparent or translucent, colorless or colored, glossy or matte, protecting from physical impact and / or dust, enlightening, anti-glare, etc.

Their disadvantage is the occurrence of glare that interferes with the observer. For example, on convex screens of cathode ray displays, due to partial reflection from their surfaces, spurious images of all objects in front of them are visible, and bright objects give images that are perceived as glare.

Examples of technical screens include car windows, cabin lights of aircraft and swimming vehicles, protective transparent screens of shop windows, windows, displays, dashboards, windows, etc., as well as opaque screens. Glare from their surfaces also interfere with the observer and / or tire him.

To reduce glare, different single-layer and multilayer coatings, films, including removable (e.g., US Pat. No. 3616098, 7764580, 4172613, 4746162, 4759581, 4873120, 5165462), and additional screens (e.g., US Pat. No. 2076397, 4246613, 4548472) using diffraction, polarizing and other optical effects . The disadvantage of these measures is the need to introduce additional layers, which also bring their own shortcomings (for example, a glare-free additional screen in front of the monitor reduces the image brightness, reduces usability, etc.).

The aim of the invention is to reduce glare from the screen.

This goal is achieved by the fact that the screen surfaces visible to the observer - both information carriers and auxiliary ones - all or part of them, are made concave with a radius of curvature R ranging from 2L to 2d (2L <R <2d), where L is the distance from the screen to the observer, and d is the distance from the screen to the nearest object, the glare visible to the observer from which the screen needs to be weakened.

The radius of curvature of the surface of different elements of the screen, as well as for different areas within the same element may differ within the above limits.

The invention is based on removing from the field of view of an observer, for example a pilot, images of all bright (glare) objects or blurring these images for the observer.

Concave surfaces of screen elements form spurious images of objects like spherical mirrors with focal length F = R / 2, incl. bright objects responsible for the appearance of glare. In this case, imaginary spurious images of objects located at a distance less than the focal length from it are formed behind the screen. Valid spurious images of other objects, i.e. located at distances greater than the focal length, are formed at distances greater than the focal length from the screen. Therefore, an observer located less than the focal length from the screen sees sharp only imaginary (located behind the screen) spurious images of objects located less than the focal length from the screen, i.e. objects located between him and the screen, but in this interval bright objects are usually not located, because they can blind an observer more than any glare. Actual images of more distant objects are formed behind the back of the observer and are not visible to him or are blurred due to blur, which eliminates glare or weakens them.

If the nearest bright object, the highlight of which is to be eliminated or weakened, is at a distance d> L, then the radius of curvature of the reflecting concave surfaces of the screen elements should be less than 2d. Moreover, this object is behind the focus of the reflecting surface and does not create a sharp image visible to the observer.

Another positive quality of the proposed concave screen is that the imaginary spurious image of an object located at a distance less than the focal length is located at a greater distance from the optical axis than the object itself, i.e. may be on the periphery of the observer's field of vision or outside his field of vision.

A variant of the invention is the proposed screen, all surfaces of which are smooth (glossy), and not matte. The option is highlighted, because the matte surfaces used sometimes in screens for different purposes can distort the surface shape so that microroughness greater than the light wavelength will violate the requirements for sphericity of the surface, and this can lead to glare, although weaker ones.

An example of a specific implementation can serve as a liquid crystal display with a spherical concave shape for the cockpit. All layers of the screen have the same radius of curvature: the light guide, the back polarizer, the back wall, the layer of thin-film transistors, the liquid crystal layer, the filter layer, the front wall, the front polarizer, the antireflective film, a protective glass with an antireflection coating and a tribolayer. The screen has dimensions of 320 × 230 mm. The screen is given a spherical concave shape, and the radius of curvature is 1.2 m. (An option is a screen in which only the protective glass with its coatings has a spherical shape - while the brightness of the glare is several times lower than with a flat protective glass.) from the pilot’s eyes to the screen, equal to 0.5 m, the pilot does not see or sees significantly weakened glare from the sun and clouds, as well as from the elements of the cockpit. The luminous and glare parts of the control panel or other elements of the cockpit or the pilot’s suit are located far from the optical axis of the concave spherical mirror formed by the screen, and their imaginary images are even further from the optical axis, so glare is out of the pilot’s field of view, i.e. he is not visible and does not interfere. The method of giving the screen a concave spherical shape is the know-how of the applicant.

Another example of a specific implementation is the helicopter cockpit glazing (tandem version), in which the windows in each window have a concave (relative to the pilot) shape with a radius of curvature R = 2.0 m. With this form of glass, glare from the sun and clouds is weakened, t .to. their images are not visible or blurry, as well as glare from signal and information devices, because their imaginary images are located far from the optical axis of spherical glasses, i.e. out of sight of the pilot. Glasses are given the desired shape by lamination.

Claims (2)

1. A screen in which one, several, or all surfaces visible to the observer are concave with a radius of curvature R ranging from 2L to 2d (2L <R <2d), where L is the distance from the screen to the observer, ad is the distance from the screen to the nearest object, visible to the observer, glare from which the screen needs to be eliminated or weakened. 2. The screen according to claim 1, characterized in that the reflective surface or reflective surface of the screen is made glossy.