JPH01274302A - Flat type lighting device - Google Patents

Abstract

PURPOSE:To obtain bright illumination with a small power consumption by forming a reflection means so that the light quantity irradiated from one side surface of an illumination plate is more than that irradiated from the other surface. CONSTITUTION:The light gone out from a light source 1 enters into an illumination plate 2, repeatedly reflected at individual parts, goes out from the upper surface 2a or lower surface 2b of the plate 2, and lights the vicinity. The light reflected at the lower surface part 3a2 is again reflected at the upper surface part 3a1 and goes out from the lower surface 2b of the plate 2 since the part 3a1 is expanded to the inner side than the part 3a2 in the reflection means 3a of one end. The reflection means 3b of the other end is the same. Consequently the light quantity gone out from the surface 2b of the plate 2 is more than that from the surface 2a. And the light of the source 1 is used without uselessness for lighting a document 5 compared to the case where the light quantity gone out from both surfaces is equaled, and bright illumination is obtained with small power consumption.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a flat type device that is used when it is necessary to prevent light from leaking into the surroundings, such as when reading indentations in a bedroom or when reading materials during a conference projection. This invention relates to a lighting device.

[Conventional technology]

Conventionally, in order to prevent light from leaking into the surrounding area, stand-type lighting equipment has been used in bedrooms, and small spotlights have been used on airplanes, night trains, etc.

However, since these require a certain distance from the light source to the object to be illuminated, the light is largely diffused into the surroundings, brightening unnecessary areas. Furthermore, the power consumption of the light source is large and portability is poor.

Furthermore, although a pencil-shaped spotlight is sometimes used, the illumination range is narrow and the user must move the book while reading, making it inconvenient to use.

Conventionally, a flat lighting device shown in FIG. 24 has been proposed as a solution to such problems.

In this, a light fi 51 is provided at one end of a transparent illumination plate 52,
By reflecting the light 'rA51 by the reflecting means 53 at the edge of the illumination plate 52, the illumination plate 52 is illuminated from the upper and lower surfaces.

According to this, by placing the illumination plate 52 on an object to be illuminated, such as a book, the object to be illuminated can be illuminated with light emitted from the bottom surface of the illumination plate 52, and the object to be illuminated can be read through the illumination plate 52. can. Therefore, there is little light leakage to the surroundings, power consumption is relatively low, and a wide range of objects to be illuminated can be illuminated. Also, if the object to be illuminated is thin memo paper, etc.,
It can be placed on the lighting board 52 and illuminated from the back side for reading and writing.

[Problem to be solved by the invention]

In this type of flat illumination device, when the illumination plate 52 is placed on an object to be illuminated, there is no need for light to be irradiated from the top surface of the illumination plate 52, and when the illumination plate 52 is used to be transmitted through the illumination object for reading, the illumination plate 52 There is no need for light to be emitted from the bottom surface.

On the other hand, the reflection means 53 is a portion 53 that covers the upper surface of the illumination plate 52.
1 and the portion 53□ covering the lower surface have the same width, and light is distributed approximately equally to the upper and lower surfaces.

Therefore, when an object to be illuminated is placed on either the upper or lower surface of the illumination plate 52, half of the light from the light source 51 is wasted, resulting in insufficient illuminance. Increasing the illuminance increases power consumption.

If the power consumption increases, the usage time will become shorter when a secondary battery or the like is used as a power source, or the battery will become larger, resulting in poor usability.

An object of the present invention is to provide a flat lighting device that can prevent light from leaking to the surroundings, use light to illuminate objects without waste, and provide bright illumination with low power consumption.

[Means to solve the problem]

The present invention provides a flat lighting device in which a light source is provided at one end of a transparent lighting plate, and reflecting means is provided on an end face and at least a part of the edge of the lighting plate, in which one side and the other side of the lighting plate are provided. The distribution amount of light emitted from the light source is varied depending on the reflecting means.

[Effect]

According to the configuration of this invention, the light from the light source enters the illumination plate, is reflected by the reflecting means, and is irradiated from both sides of the illumination plate.

The illumination plate is placed above a document or the like to be illuminated, and a document or the like illuminated with light emitted from the bottom surface can be seen through the transparent illumination plate.

You can also read and write by placing a thin piece of paper on top of the lighting board and lighting it from the back.

The amount of light distributed by the light source is different on both sides of the illumination plate, but when an object to be illuminated is placed either above or below the illumination plate, the side with a larger amount of light distributed faces the object to be illuminated.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 and 2. A shaft-shaped portion 2 is attached along one end of a transparent rectangular illumination plate 2.
c is provided, and a light source l is embedded in a hole penetrating the annular portion 2c. Both sides 2a of the lighting board 2.

Reflection means 3a, 3b, and 3c (see FIG. 2) are provided on a pair of opposing edges and four end faces of the mirror 2b, respectively. 5
is a document to be illuminated, which is placed on the desk 40.

The reflecting means 3a, 3b at one end and the other end of the illumination plate 2 have upper surface portions 3al, 3b+ that cover the upper surface 2a of the illumination plate 2, and lower surface portions 3a, 3b+ of the illumination plate 2, respectively.
The length 2. is inward from the lower surface portions 3ag and 3bt that cover b.
They are each formed to extend by l'.

The reflecting means 3a, 3b, and 3c are made of polished metal plates, metal plating, vapor deposition, or the like.

Reflection means 3a, 3b, 3 are formed by directly roughening the illumination plate 2.
The illumination plate 2 may be made of resin such as acrylic or glass.

The light source l consists of an incandescent lamp or the like.

When using this flat illumination device, the document 5 is viewed by placing the illumination plate 2 directly on the document 5 as shown in FIG. 1, or by placing a thin piece of paper on the illumination plate 2 for reading and writing.

The light emitted from the light source 1 enters the illumination plate 2, is repeatedly reflected at each part, and exits from the upper surface 2a or lower surface 2b of the illumination plate 2, illuminating the vicinity thereof. Reflection means 3a.

3b and 3c eliminate the leakage of light to the surroundings and concentrate the light from the light source 1 on the necessary areas.

The reflecting means 3a at one end has an upper surface portion 3a and a lower surface portion 3a.
Since it is expanded inward from point t, the lower surface portion 3a! The light reflected by the upper surface part 3a+
It is reflected again and exits from the lower surface 2b of the illumination plate 2. The same applies to the reflecting means 3b at the other end. Therefore, the lower surface 2 of the illumination plate 2
The amount of light emitted from the upper surface 2a is greater than the amount of light emitted from the upper surface 2a. Therefore, compared to a case where the amount of light emitted from both sides is equalized, the light from the light source 1 is used without waste for illuminating the document 5, and the document 5 can be brightly illuminated with less power consumption.

Since power consumption is reduced, when a battery is used as a power source for the light Al, it can be used for a long time even if the battery capacity is small, and the battery is made smaller and more portable.

Further, since the upper surface portion 3a+ of the reflecting means 3a on the side of the light 61 is widened inward, there is an advantage that the light emitting part of the light source 1 does not directly enter the eye. Reflection means 3b on the opposite side to the light source l
The reason why the upper surface portion 3b+ of the lighting board 2 is made wider inward is that
This has the advantage of preventing concentrated reflections from the end surfaces of the document 5 from entering the eyes, thereby making the document 5 easier to see.

When paper is placed on the illumination plate 2, the paper placed on it can be efficiently illuminated by making the side with a large amount of light face upward.

In this way, the light leakage to the surroundings is minimized, the object to be illuminated can be efficiently illuminated with a small amount of electric power, and portability and usability are improved. Therefore, this flat lighting device can be used, for example, in the following applications. ■Reading in the bedroom 1 Writing letters and memos. ■Reading materials when projecting slides at academic conferences, seminars, etc., or giving lectures using 011P. ■Reading on airplanes and night trains. ■It can be used as a car navigation light for writing notes, etc.

In the embodiment described above, the reflecting means 3a and 3b were provided only on one pair of edges on both sides of the illumination plate 20, but reflecting means may be provided on the remaining pair of edges as well.

The reflecting means may be provided only on one side of the illumination plate 2.

Further, in the above embodiment, since the sights are different on both sides of the illumination plate 2, the upper surface portions 3a+, 3b of the reflecting means 3a, 3b
+ and the width of the lower surface portion 3a2.3bzO are changed, but the amount of light may be made different by keeping the width the same and changing the angle, etc.

Next, other embodiments will be described. These are the same as in the first embodiment unless otherwise specified.

3 to 5 show the second to fourth embodiments, respectively. In the example shown in FIG. 3, the light source 1 is brought into contact with the end surface of the illumination plate 2. In the example shown in FIG. 4, a groove 2d is provided in the shaft-shaped portion 2c of the illumination plate 2 to accommodate the light source 1.

In the example shown in FIG. 5, the cross-sectional shape of the end 2e of the illumination plate 2 opposite to the light source 1 is arcuate.

FIG. 6 shows a fifth embodiment, in which a shaft-shaped portion 2c of the illumination plate 2 is provided with a contact piece 2f that protrudes against the document 5.

FIG. 7 shows a sixth embodiment. In this example, a planar magnifying lens 6 made of a Fresnel lens or the like is provided.

The magnifying lens 6 has one end rotatably attached to the end of the illumination plate 2 with a support shaft 7, and a rotating leg 9 rotatably attached to the other end with a support shaft 8. The rotating leg 9 can be held at any desired angle by the friction of the mounting portion of the support shaft 8.

With this configuration, the object to be illuminated can be seen through the magnifying lens 6. Furthermore, by changing the angle of the rotation IJ59, the inclination angle of the magnifying lens 6 can be varied as shown by the chain line in the figure.

When the inclination angle of the magnifying lens 6 changes, the distance from the document or the like (not shown) on the lower or upper surface of the illumination plate 2 to the magnifying lens 6 changes, and the magnification changes.

Therefore, it is convenient for the following uses. For example, when viewing from a relatively low position of the eyes 41, such as when reading in bed, the magnification in the distance increases, making it easier to read documents and the like. In this case, as the angle is increased, the document can be viewed from a lower position. Furthermore, since the magnifying lens 6 is tilted, no blind spot occurs due to total reflection even when viewed from an angle, unlike when the magnifying lens 6 is parallel to a document or the like. Since the magnifying lens 6 is thus attached to the illumination plate 2 and can be rotated to adjust the magnification, it is easier to use than when viewing while holding and adjusting a separate magnifying lens. If the magnifying lens 6 is not needed, move it toward the front.

FIG. 8 shows a seventh embodiment. In this example, the magnifying lens 6
and the illumination plate 2 are connected by a lever 11 in the form of a parallel link. 7', 8', and 10 each indicate a support shaft of the lever 11.

In this example, by changing the angle of the lever 11, the distance between the magnifying lens 6 and the illumination plate 2 is changed while keeping it parallel.
You can change the magnification. Since they are parallel, the entire surface of the document 5 can be viewed at equal magnification. This example is suitable for reading document 5 from relatively upward.

9 to 11 show an eighth embodiment.

In this example, a pair of U-shaped pivoting legs 12 are attached to both ends of a magnifying lens 6 so as to be rotatable around a support shaft 10.The pivoting legs 12 are made of an elastic material, and their elasticity allows them to The illumination plate 2 is mounted between the pieces 12a in a pressure-contact state. On the inner surface of each leg piece 10, there is a non-slip part 1 made of rubber or the like with a large frictional force.
3 to eliminate slippage against the illumination plate 2.

When configured in this way, the distance to the illumination plate 2 is adjusted in both the inclined position and the parallel position of the magnifying lens 6,
You can change the magnification. Further, the magnifying lens 6 can be easily attached and detached.

12 to 14 show a ninth embodiment.

In this example, support pieces 14 and 15 are fixed to both ends of the magnifying lens 6, and a rotating support member 16 made of a wire spring and serving as a handle is provided on the shaft-shaped portion 2C of the illumination plate 2. The inwardly projecting portions of both ends of the rotary support member 16 fit into the holes of the illumination vi2 and are rotatably supported, and the angle can be maintained by elastic pressure contact. The supporting pieces 14 and 15 have various protruding lengths a to d from the magnifying lens 6, such that a>b>c>d.

In this example, the difference in the protrusion length axd of the support members 14 and 15 is utilized, for example, as shown in FIG. 14(A).

By changing the attitude of the magnifying lens 6 from front to back and front to back as shown in FIG. 3B, and by changing the angle of the rotation support member 16, the distance and angle of the magnifying lens 6 with respect to the illumination plate 2 can be variously changed.

It is also possible to change the distance of the magnifying lens 6 while keeping it parallel to the illumination plate 2. Further, the magnifying lens 6 can be easily attached and detached.

15 to 17 show a tenth embodiment. In this example, a stand 17 for supporting the illumination plate 2 is provided. The stand 17 is formed by bending a pair of standing pieces 18,
A plurality of holes 19 are provided in the standing piece 18. The lighting board 2 is °
It has a slit-like hole 20 into which the standing piece 18 is fitted, and a ball 21 biased by a spring 22 is provided in a horizontal hole therein as shown in FIG. 23 is a set screw for the spring 22.

According to this configuration, the lighting board 2 can be set at a desired height by engaging the ball 21 with any hole 19 of the standing piece 18. By holding the illumination plate 2 in this way, a gap is created between the document 5 and the illumination plate 2, so it is not necessary to lift the illumination plate 2 when turning the pages of the document 5, making page turning easy. can be done.

FIG. 18 shows an eleventh embodiment. In this example, a guide groove 20' is provided in place of the slit-like hole 20 of the illumination plate 2 in the example of FIG. A hole 19' is provided.

A locking ball is provided on the standing piece 18 side.

19 to 21 show a twelfth embodiment. In this example, a lever 27 is rotatably attached to a bent piece 26 provided on a stand 24 with a support shaft 28, and a hole 27 at the upper end of the lever 27 is attached.
9 is rotatably engaged with the boss portion 29' of the illumination plate 2. The dimension a' of the lever 27 is such that a gap is created between the document 5 placed on the stand 24 and the illumination plate 2 so that the pages can be turned over. The lower end 27a of the lever 27 extends by a distance b' that makes the stand 124 tilt from the top surface of the desk 40. A hook 25 provided at the front end of the stand 24 is used to prevent the document 5 from slipping off due to the inclination of the stand 24.

In this configuration, the document 5 can be held diagonally, so the second
As shown in Figure 1, it is easier to see when viewing with the eyes 41 in a diagonally forward position.
Lift it up as shown by the chain line in Figure 1. Since the illumination plate 2 is rotatably supported at one end, it is easy to turn the pages.

FIGS. 22 and 23 show a thirteenth embodiment. In this example, as a power source for the light source 1 of the lighting board 2, a power adapter 30 that steps down and rectifies a commercial power source is provided. A plug 34 serving as an output terminal of the power adapter 30 is connected to an inlet (jack) 35 provided on the lighting board 2. The lighting board 2 has a built-in secondary battery 32, a slide-operated lighting switch 31, and an interlocking switch 33.

The interlock switch 33 opens when the plug 34 is inserted into the receptacle 35. When the lighting switch 31 is turned to the terminal 31a side, the light source 1 is directly lit by the current from the power adapter 30 when the power adapter 30 is connected. When the power adapter 30 is not connected, the light source 1 is turned on by the current from the secondary battery 32.

When the lighting switch 31 is turned on to the terminal 31b side, the light source 1 is turned off. At this time, if the power adapter 30 is connected, the secondary battery 32 is charged.

In this way, the lighting by the built-in secondary battery 32 and the commercial
Since both direct lighting and lighting using one source can be performed, the usability of the lighting board 2 is improved. Moreover, since the lighting switch 31 can be turned on and off in both cases, operability is good.This embodiment can be configured in combination with each of the above-mentioned embodiments.

(Effects of the Invention) In the flat lighting device of the present invention, a light source is provided at one end of the transparent lighting plate, and the light is emitted from the surface of the lighting plate.
Only the object to be illuminated can be illuminated by eliminating light leakage to the surroundings. In this case, since the amount of light emitted from one side of the lighting plate is made larger than the amount of light emitted from the other side using a reflection means, by directing the side with a large amount of light toward the object to be illuminated, the light from the light source is wasted. It can be used to illuminate objects without needing to be illuminated. Therefore, there is an effect that bright lighting can be achieved with low power consumption.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the first embodiment of the present invention, FIG. 2 is a perspective view of the illumination plate, and FIGS.
FIG. 6 is a perspective view of the fifth embodiment, FIG. 7 is a side view of the sixth embodiment, and FIG.
The figure is a side view of the seventh embodiment, FIG. 9 is a perspective view of the eighth embodiment, FIG. 1O is a side view thereof, and FIG. 11 is an XI of FIG.
-XI line sectional view, FIG. 12 is a perspective view of the ninth embodiment, FIG. 13 is a side view thereof, FIG. 14 is an explanatory diagram of its operation, and FIG. 15 is a side view of the 10th embodiment, FIG. 16 is an exploded perspective view thereof, FIG. 17 is a sectional view thereof, FIG. 18 is a partial perspective view of the illumination plate in the eleventh embodiment, and FIG. 19 is an exploded perspective view of the twelfth embodiment. Figure 20 is a perspective view of the device in use, Figure 21 is a side view of the same, Figure 22 is a perspective view of the 13th actual flow side, Figure 23 is its electric circuit diagram, and Figure 24 is a conventional example. FIG. ■... Light source, 2... Illumination plate, 3a to 3C... Reflection means, 3a+, 3b+- upper surface portion, 3at, 3bz-
・・Bottom surface part, 5・・Document, 6・・Magnifying lens, 9
... Rotating leg, 14.15... Support piece, 16... Rotating support member that also serves as handle, 17.24... Stand Fig. 2 Fig. 3 Fig. 4 X bz Fig. 5 Figure 7゛] U Figure 9 Figure 10 Figure 11 Figure 15 Figure 16 Figure 18 Figure 19

Claims (1)

[Claims] In a flat lighting device, a light source is provided at one end of a transparent lighting plate to irradiate light into the interior of the lighting plate, and a reflecting means is provided on an end face and at least a part of the edge of the lighting plate. A flat lighting device characterized in that the reflecting means is formed so that the amount of light emitted from one surface is greater than the amount of light emitted from the other surface.