JPS6172220A - Glasses lens for observation of crt display device - Google Patents

Abstract

PURPOSE:To reduce the fatigue of eyes and the degradation of the visual acuity of an operator by extending an apparent sight distance of a CRT display placed at a close distance to observe the CRT display at the best sight distance for the operator and correcting the vergence angle simultaneously. CONSTITUTION:Glasses lenses 4 and 5 consisting of parts of one convex lens whose optical axis is the middle point of a segment connecting centers of pupils of eyes 1 and 2 are arranged just before eyes 1 and 2 to form a virtual image of a CRT display device in the position a length l' distant from eyes (the length l' is longer than a length l from eyes to the CRT display device). When the CRT display device 3 is observed through this convex lens, not only the diopter but also the vergence angle is corrected simultaneously. Thus, the CRT display device 3 is observed in the natural vergence and control state.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spectacle lens having the effect of reducing eye strain and visual acuity deterioration when viewing a CR or T display.

Conventional techniques and their problems In recent years, with the spread of office automation equipment, operators' blurred vision and decreased visual acuity have become major social problems.In order to prevent such health problems, the Ministry of Labor has issued a A work stoppage of 15 minutes to 15 minutes is provided, and the viewing distance is 40 minutes.
Although there are indicators such as ~60cm as a guideline, it is not polite to observe work down time in companies, and even at home, there are cases where children are so absorbed in their computers that they forget the time when operating them. many. In addition, due to the competition for the number of pits, the characters have become smaller, and it is difficult to maintain an appropriate viewing distance due to the screen becoming white and flickering due to the reflection of external light. be. .

In response to these circumstances, various types of filters and glasses that are installed just in front of the CRT display have been proposed and put into practical use in order to weaken the light emitted from the CRT display and eliminate diffuse reflection, but little consideration has been given to the viewing distance of the CRT display. It had not been done.

When detecting a CRT display, the distance between the CRT display is 40 to 60 cm, which is extremely close compared to a consumer TV.
The operator has to keep looking at the display, but this short viewing distance is thought to be a cause of eye strain and especially poor visual acuity, and if we focus on the fact that most of the visual acuity loss among operators is due to pseudomyopia, CRT... It is thought that visual acuity deterioration can be alleviated by increasing the apparent viewing distance of r-spray.

Purpose The present invention has been made in view of the above-mentioned points, and provides a spectacle lens that increases the apparent viewing distance of a CRT display located at a close distance and enables WA viewing of a CART display at an optimal viewing distance for an operator. The purpose is to provide.

Structure of the Embodiment First, the structure of the eyeglass lens for CRT display a according to the present invention will be explained based on FIG.

When the distance between the pupils of both eyes is L, the convergence angle O1 is expressed by the following equation.

θ (=2 Lan-' L/21 - (L) On the other hand, if the focal length of the eyeball when observing at infinity is f, then the focal length of the eyeball when looking at the CRT display 3 at a distance of 1 mQ is f ′ is expressed by the following formula.

f' = Q - f/ (Q + f) ...
...(2) For example, the distance Q to the CRT display 3 is 400 mm + the focal length of the eyeballs when observing at infinity = 17 mm, and the distance between the pupils of both eyes L =
62.5h+n+ +m from formula (1) and formula (2)
Tracking angle θ1. Determining the focal length f', θ1: 8.93' f ' = 16.31 m
m. At this time, the eyeballs 1 and 2 are tilted inward by approximately 4 and 5 degrees, and the focal length is approximately Q, 7 mm shorter, and 40 c.
It can be seen that even at a viewing distance of +++, a considerable burden is placed on the eyes.

Here, eyeglass lenses 4 and 5 are made of a single convex lens whose optical axis is the midpoint of a line segment connecting the pupil centers of the eyeballs 1 and 2.
By arranging the CRT display 3 directly in front of the eyeballs 1 and 2, a virtual image of the CRT display 3 can be created at Q' which is further away than the distance Q. This eye Ql.

When observing the CRT display 3 through a convex lens whose optical axis is the midpoint of the line segment connecting the pupil centers of 2, not only the diopter but also the width angle are corrected at the same time, resulting in natural alignment and adjustment. In this state, the CRT display 3 can be observed wA.

If spectacle lenses for farsightedness were placed in the positions of spectacle lenses 4 and 5, the diopter would change but the convergence angle would not, which would upset the balance between convergence and accommodation, and as a result, the operator would have to He will complain of fatigue.

The feature of the present invention is that the diopter and the angle of convergence are corrected at the same time. 1. By using the spectacle lens for CRT display viewing according to the present invention, the CRT display 3 at a distance Q can be viewed without reducing the viewing angle. Since the CRT display 3 can be moved away at a distance Q', observation can be made in the same state of convergence and accommodation as when the CRT display 3 is actually located at Q'.

The focal length F and the convergence angle 02 of the CRT display viewing spectacle lenses, ie, the spectacle lenses 4 and 5, can be determined by the following equations.

F = 1+, - Sad' / (Q' -Q)
...(3) (j 2 = 2 an-"
L/2 Q'==
・('I) Using the above formulas (3) and (4), 1For example, α=1100 units 1111°Q' = 100On+m
When calculating the focal length F and the angle of intersection θ2 assuming that, F = 666.67 mm, fl 2 = 3
．． 58', and by wearing a spectacle lens consisting of a convex lens portion with a focal length of about 670 mm, it becomes 40.
Even if you look at CRT display 3 at a distance of cm, l m
When looking at a CRT display at a distance of If the power of the lens is too strong, it will be a burden on the user, so the focal length is generally 11,200 m.
It is desirable to use a convex lens in the range of m to 2000 mm.

2 to 8 show a CRT display I according to the present invention.
! 11 is shown for implementation when using as a spectacle lens for ophthalmology.

Figures 2 and 3 show an example of the case where the glasses are assembled into an eyeglass frame, and are made of a single convex lens whose optical axis is the midpoint of a line connecting the pupil centers of both eyes. The lenses 4 and 5 are used by being incorporated into the eyeglass frame 6 in the same way as lenses for nearsightedness or farsightedness.

FIGS. 4 to 6 show an embodiment in which the eyeglass adapter frame 7 is used by incorporating it into an eyeglass adapter frame. [H'i! Frame part 10a of IO
It is used by being fixed to the glasses 10 by holding it in place.

Figures 7 and 8 show an example of the case where it is used by incorporating it into Heradolupe, and it incorporates a single convex lens 11 whose optical axis is the midpoint of a line connecting the pupil centers of both eyes. A hair band 13 is attached to the supporting member 12, which is shaped like a head magnifying glass.

Example! 7) (’! I”M- Next, the operation of the above embodiment will be explained.

As shown in FIGS. 2 and 3, when the spectacle lenses 4 and 5 for observing a CRT display are incorporated into the spectacle frame 6, the design of the spectacle frame 6 can be freely selected like a normal spectacle frame. It can be used without any discomfort.

In addition, even for eyeglass users, the eyeglass lenses 4 and 5 can be assembled into the eyeglass adapter frame 7 as shown in FIGS. By using the present invention, the CRT display II of the present invention can be used for eyeglass lenses.

Furthermore, if the structure is shaped like a head magnifying glass as shown in FIGS. 7 and 8, the distance from the eyeball to the convex lens 11 will hardly change, making it useful even in cases where it is uncomfortable to wear glasses. As described above, according to the present invention, by increasing the apparent viewing distance of a CRT display located at a close distance, it becomes possible for an operator to observe the CRT display at an optimal viewing distance, and at the same time, the angle of convergence also increases. Since this is corrected, it is possible to reduce eye strain and visual acuity deterioration for the operator.

Furthermore, if the spectacle lens for CRT display viewing of the present invention has a polarizing effect, a light reduction effect, an ultraviolet ray removal effect, etc.,
It is clear that the effects of filters, spectacle lenses, etc., which have been conventionally used for viewing CRT displays, are also achieved, making it possible to further reduce eye strain.

[Brief explanation of drawings]

FIG. 1 is a diagram of a CRT display wt observation eyeglass lens according to the present invention, FIG. 2 is a top view showing a state in which the CRT display observation eyeglass lens according to the present invention is assembled into an eyeglass frame, and FIG. 4 is a front view showing the state in which the eyeglass frame adapter is assembled, FIG. 5 is a side view, FIG. 6 is a side view showing the state in which the eyeglass frame adapter is attached to the eyeglasses, and FIG. FIG. 8 is a top view showing a state where it is assembled into a head rube, and FIG. 8 is a front view of the same. 1.2... Eyeball 3... CRT display 4.5... Eyeglass lens 1 diagram

Claims (1)

[Scope of Claims] 1. A spectacle lens for observing a CRT display, characterized in that it consists of a single convex lens whose optical axis is the midpoint of a line connecting the pupil centers of both eyes. 2 The focal length of the above convex lens is from 200mm to 2000mm.
2. A spectacle lens for viewing a CRT display according to claim 1, wherein the lens has a diameter of between 1 and 2 mm.