JPH08317901A - Stereoscopic chart plate - Google Patents

Abstract

PURPOSE: To simplify the fabrication of a chart plate by disposing a pair of polar screens, which are put on top of each other with their respective polarizing axes forming an anale of 90 deg., and forming identically shaped chart holes, which are shifted as far as a parallax is produced in the pair of polar screens. CONSTITUTION: Identically shaped chart holes 14L and 14R, which are shifted by a distance Δ to produce a parallax, are respectively formed as a polarizing pattern in a pair of polar screens 12L and 12R. A part i, where both holes are put on each other, does not transmit light from a lamp 11, and therefore, looks dark. Light transmit a part ii where the polar screen 12R faces the chart hole 14L. Respective light beams transmitted through the parts ii and iii differ from each other by 90 deg. in polarizing direction, and simultaneously, are made respectively equal to the polar screens 13L and 13R in polarizing direction. The light beam transmitted through the part iii of the polar screen 12L is visually confirmed through the polar screen 13L by the left eye EL of an inspectee. The light beam transmitted through the shifted part of the polar screen 12R is visually confirmed through the polar screen 13R through the right eye ER of the inspectee.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic chart plate in which a pair of charts whose polarization axes are shifted by 90.degree.

[0002]

2. Description of the Related Art As a stereoscopic chart plate of this type,
For example, as shown in FIG. 3 (c), for example, a glass plate 1 having a minute square shape has the same polarization pattern (polarization chart).
A chart board A provided with a few is considered.

The polarization patterns 2 and 3 are patterned holes 2a and 3a by etching or the like on the glass plate 1 as shown in FIG. 3 (a).
(Slit-shaped hole in the figure) is formed, and this pattern hole 2
The polarizing filters 2b and 3b are attached to the glass plate 1 so as to cover a and 3a. The polarization directions (polarization axes) of the polarization filters 2b and 3b are deviated from each other by 90 °.

At the time of a stereoscopic inspection using such a chart plate A, the chart plate A is illuminated by a lamp 4 from the back side so that the polarized light flux transmitted through the polarizing filters 2b and 3b is passed through the polarizing filters 5 and 6. The left and right eyes EL and ER of the subject are visually recognized. At this time, the polarized light beam (polarization pattern 2) that has passed through the polarization filter 2b and is polarized is visually recognized by the left eye of the subject through the polarization filter 5 whose polarization axis is in the same direction as that of the polarization filter 2b. The polarized light beam (polarization pattern 3) that is transmitted through the filter 3b and is polarized has a polarization axis of the polarization filter 3b.
It can be visually recognized by the right eye of the subject through the polarization filter 6 in the same direction.

As a result, the subject is made to combine the polarization patterns 2 and 3 visually recognized by the left and right eyes in the brain so that the combined pattern looks three-dimensional. The position where the synthetic pattern appears can be determined by the position (a) in FIG. 3 (a) or the position (b) in FIG. 3 (b). .

[0006]

By the way, in the above-mentioned chart plate A, the pattern holes 2a and 3a are provided adjacent to each other with a slight difference in parallax.
The polarizing filters 2b and 3b covering a are attached to the glass plate 1.

However, the chart plate A has a size of 1 cm × 1.
The glass plate 1 having a size of about 1 cm is provided with a plurality of pairs (pairs) of very small patterns of about 1.5 mm to 3 mm, and the pattern holes 2a and 3a and the interval Δ are very small, for example, about 5/100 mm. Therefore, for example, it is very difficult to attach the polarizing filters 2b and 3b covering the pattern holes 2a and 3a of the chart plate A to the glass plate 1, and it is not easy to manufacture the chart plate A. It was

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a chart plate for stereoscopic vision which can be easily manufactured.

[0009]

In order to achieve this object, according to the present invention, a pair of polarizing filters are provided with their polarizing axes shifted by 90 ° and overlapped with each other, and the pair of polarizing filters are shifted by an amount corresponding to parallax. It is characterized in that it is a stereoscopic chart plate having chart holes of the same shape.

[0010]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 (a) is an explanatory view for schematically explaining an optometry system using a stereoscopic chart plate according to the present invention, and FIGS. 1 (b) and 1 (c) are FIG. 1 (a). 3 is an explanatory view of the stereoscopic chart plate shown in FIG.

In FIG. 1A, 11 is a lamp which is a light source, 12 is a chart plate for stereoscopic vision according to the present invention, and the lamp 11 and the chart plate 12 for stereoscopic vision are arranged in a chart box (not shown). . Also, 13L, 13
R is a polarizing filter arranged in front of the left and right eyes EL, ER of the subject, and is arranged between the left and right eyes EL, ER of the subject and the chart viewing window (not shown) of the chart box. It is provided in the left and right optometry units of the subjective optometry device (not shown). Moreover, the polarization filters 13L, 13
Rs are provided such that their polarization directions (polarization axes) are offset from each other by 90 °.

The stereoscopic chart plate 12 is composed of a pair of polarizing filters 12L and 12R which are superposed with their polarization directions (polarization axes) shifted by 90 ° from each other, and the polarizing filters 12L and 12R are fixed to each other. . In addition, the polarization filters 12L and 12R have the same shape chart holes 14L, which are shifted by an interval Δ that causes parallax.
14L is formed as each polarization pattern.

At the time of a stereoscopic inspection using such a stereoscopic chart plate 12, by illuminating the stereoscopic chart plate 12 from the back by a lamp 11, the light flux transmitted through the stereoscopic chart plate 12 is polarized. Filter 13L, 1
It is visually recognized by the left and right eyes EL and ER of the subject through 3R.

At this time, the polarizing filter 1 as shown in FIG.
The overlapping portion (i) of 2L and 12R is the lamp 1
Light from 1 does not pass through, so it looks dark.

Further, in the portion (ii) of the polarizing filter 12R which faces the chart hole 14L, light is transmitted, but this portion
The light beams transmitted through (ii) and (iii) have their polarization directions (polarization axes) deviated from each other by 90 °, and the polarization filters 13L,
Since 13R and the polarization direction (polarization axis) are made to coincide with each other, the light flux transmitted through the portion (iii) of the polarization filter 12L is transmitted through the polarization filter 13L to the left eye E of the subject.
The light beam visually recognized by L and transmitted through the portion (iv) of the polarization filter 12R is visually recognized by the left eye ER of the subject through the polarization filter 13R.

As a result, the chart holes 14L and 14R visually recognized by the left and right eyes EL and ER are made to be synthesized in the brain by the subject, so that the synthesized pattern can be seen three-dimensionally. Then, the state of the stereoscopic function of the subject can be determined based on the position where this composite pattern appears.

<Modification> FIG. 2 shows a modification of the stereoscopic chart plate 2 according to the present invention. The stereoscopic chart plate 2 is provided with a plurality of chart patterns P1 to P4 having different shapes. Has been. The chart patterns P1 to P4 are basically the same as the stereoscopic chart plate 2 shown in FIG. 1 except for a part, and therefore, the same portions or similar portions are designated by the same reference numerals. And its description is omitted.

The chart plate 2 shown in FIG. 1 shows an example in which the chart holes 14L and 14R are arranged so as not to overlap, but in the present embodiment, the chart holes 14L and 14R are arranged so as to partially overlap. The chart holes 1 of the chart patterns P1 to P4 are arranged from the left end of the polarization filter 12R.
If the distance to 4R is L1 to L4, the distance from the left end of the polarization filter 14L to each chart hole 14L of the chart patterns P1 to P4 is (L1 + Δ), (L2 +
Δ), (L3 + Δ), (L4 + Δ).

As a result, in FIG. 2 as well, similar to the above-mentioned embodiment, the portion (i) where the polarizing filters 12L and 12R overlap each other looks dark because the light from the lamp 11 is not transmitted. Moreover, light is transmitted through the portion (ii) of the polarizing filter 12L that faces the chart hole 14R and the portion (iii) of the polarizing filter 12R that faces the chart hole 14L, but these portions (ii) and (iii) are transmitted. Since the light beams have their polarization directions (polarization axes) deviated from each other by 90 ° and their polarization directions (polarization axes) are matched with those of the polarization filters 13L and 13R, respectively, the polarization filter 12L portion (ii)
The light flux transmitted through the polarization filter 13L is visually recognized by the subject's left eye EL through the polarization filter 13L, and the portion of the polarization filter 12R (i
The light flux transmitted through ii) is visually recognized by the subject's left eye ER via the polarization filter 13R.

Further, since the light flux passing through the overlapping portion (iv) of the chart holes 14L and 14R is not polarized, the right and left eyes EL and ER of the subject are polarized filters 13L and 13L.
The light flux passing through the portion (iv) is visually recognized through R.

Therefore, the chart hole 12L shown in FIG. 2A is visually recognized in the left eye EL of the subject, and the right eye ER of the subject is shown.
The chart hole 12R shown in FIG. 2 (a) is visually recognized.

[0023]

As described above, the present invention has a polarization axis of 9
Since a pair of polarizing filters which are offset from each other by 0 ° are provided and the pair of polarizing filters are formed with chart holes of the same shape which are displaced by an amount corresponding to the occurrence of parallax, the chart plate can be easily manufactured. it can.

[Brief description of drawings]

FIG. 1 (a) is an explanatory view for schematically explaining an optometry system using a stereoscopic chart plate according to the present invention, and FIGS. 1 (b) and (c) are stereoscopic views shown in (a). FIG. 1D is a sectional view taken along the line BB in FIG. 1B.

2 (a) and 2 (b) are explanatory views showing another example of the polarization filter constituting the chart plate for stereoscopic vision according to the present invention,
(c) is an explanatory view of a chart plate for stereoscopic vision formed by superposing the polarizing filters of (a) and (b), and (d) is CC of FIG. 2 (c).
It is sectional drawing which follows the line.

3 (a) and 3 (b) are explanatory views for schematically explaining an optometry system using a conventional stereoscopic chart plate.
(c) and (d) are explanatory views of the stereoscopic chart plate shown in (a) and (b).

[Explanation of symbols]

 12 ... Stereoscopic chart plate 12L, 12R ... Polarizing filter 14L, 14R ... Chart hole

Claims (1)

[Claims] 1. A stereoscopic view characterized in that a pair of polarizing filters are provided with their polarization axes shifted by 90 ° and are overlapped with each other, and chart holes of the same shape are formed by shifting the pair of polarizing filters by an amount corresponding to a parallax. Chart board.