JPH0714986Y2 - Projector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a projection device, and more particularly to a projection device for enlarging and imaging a subject such as a slide film on an external projection surface via a projection lens. .

(Prior Art) Conventionally, as this type of projection device, a structure shown in FIG. 4 is known. In the figure, reference numeral 1 denotes a casing, and a light source 2 such as a halogen lamp is provided near the back surface inside the casing.
And a concave mirror-shaped reflector 3 are arranged. Light source 2
An infrared reflection filter 4 is provided in front of the filter 4, and a condenser lens 5 and a relay lens 6 are provided in front of the filter 4. Further, a subject 7 such as a slide film can be placed in front of the relay lens 6, and a condenser lens 8 and a projection lens 9 are attached in front of it. In the figure, 7A is a projected image of the subject 7, 30 is a projection device installation surface, and 40 is a screen as an external projection surface.

In the projection device configured as described above, the light from the light source 2 is reflected by the reflector 3, condensed by the condenser lens 5 through the infrared reflection filter 4, and irradiated onto the subject 7 through the relay lens 6. . And
The light transmitted through the subject 7 is condensed by the condenser lens 8,
A projection image 7A in which the subject 7 is enlarged and inverted is formed on the screen 40 via the projection lens 9 having a predetermined magnification.

(Problems to be Solved by the Invention) In the above projection device, when the axis L of the projection lens 9 is orthogonal to the screen 40 as shown in FIG. Since they are orthogonal to each other, the projection image 7A is formed on the screen 40 by enlarging the subject 7 vertically and horizontally at a predetermined magnification. However, when it is desired to form the projection image 7A at a position higher than the installation position of the projection device, the front end portion of the projection device is tilted by an appropriate adjusting member 10 as shown in FIG. If so, the following problems occur.

That is, in this case, the axis L of the projection lens 9 does not intersect the screen 40 at a right angle but intersects at an acute angle.
7A 'is not orthogonal to the axis L, and the enlargement magnification increases as it goes upward compared to the original projected image 7A. Therefore, the subject 7 is not accurately projected and is distorted.

Such inconvenience becomes noticeable, for example, when the projection device is installed on a desk placed in the center of a large venue or at the rear, and the subject 7 is projected on the screen 40 provided at a high position in front of the venue. . On the other hand, it is conceivable that the projection device is installed at a high position, the screen 40 is tilted, or the like, but it is often physically impossible, and the distortion of the projected image 7A ′ described above is eliminated. It was difficult to do.

Further, the above-mentioned inconvenience is not limited to the case where the projection image is formed at a position higher than that of the projection device, but generally when the axis L of the projection lens 9 is not orthogonal to the projection surface, for example, from the diagonal direction in the horizontal direction to the screen 40. It also occurs when projecting. That is, even when the positional relationship between the projection device and the screen 40 when viewed from the plane is as shown in FIG. 5 and it is desired to project from the left and right ends of the venue onto the screen 40 in front of the venue, the projected image is produced by the same principle. The left half or right half of 7A 'will be distorted.

Therefore, conventionally, there is a drawback that the projection image is partially distorted due to the positional relationship between the projection device and the projection surface, and there is a problem that the installation position of the projection device is limited to obtain a distortion-free projection image. It was

The present invention has been proposed to solve the above problems, and its purpose is to obtain a distortion-free projected image even when the projection surface is higher than the projection device or is displaced to the left or right. The present invention is to provide a projection device.

(Means for Solving the Problems) In order to achieve the above object, the present invention is a projection for illuminating a subject by a light source and enlarging and forming a projected image of the subject through a projection lens on an external projection surface. In the apparatus, the projection lens is movable in a plane parallel to the subject and the projection surface in a state where its axis is orthogonal to the subject and the projection surface, and the projection lens of the projection lens can be moved through a fixed subject. Irradiation light from the light source, which is arranged on the opposite side and moves in the opposite direction as the projection lens moves, can be always condensed by the projection lens.

(Operation) According to the present invention, the light source moves in the opposite direction through the object by moving the projection lens in a plane parallel to the object and the projection surface. The irradiation light from this light source is condensed by the projection lens through the subject, so that the projection image can be enlarged and formed on the projection surface other than the extension line of the center of the projection device. At this time, since the axis of the projection lens is always perpendicular to the projection surface, the projection image is a distortion-free image in which the top, bottom, left, and right of the subject are magnified at the same magnification.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. First,
FIG. 1 is a perspective view showing a main configuration inside a projection apparatus according to the present invention, and the same components as those shown in FIGS. 4 and 5 are designated by the same reference numerals.

In the figure, a leg portion 21A is provided in front of the inside of the casing 1 having a rectangular parallelepiped shape, a column 21B attached to the leg portion 21A and movable in the horizontal direction, and an arm attached to the column 21B and movable in the vertical direction. A stand 21 composed of 21C is provided. A lens housing 22 is fixed to the tip of the arm 21C, and the projection lens 9 is attached to the lens housing 22.
Is attached, and a condenser lens (not shown) is arranged on the back surface thereof. The axis L of the projection lens 9 is orthogonal to an external screen (not shown).

Further, a subject installation plate 23 is disposed behind the lens housing 22 so as to be fixed to the bottom plate of the casing 1, and a slide film 7'having the subject 7 can be attached to and detached from the subject installation plate 23 by a known means. Has become. Here, the subject 7 is in a positional relationship that is always orthogonal to the axis L of the projection lens 9. Then, a ball joint 24 is attached near the center of the subject mounting plate 23, and the vicinity of the tip end of a rotating rod 25 penetrating the ball joint 24 is connected to the lower end of the lens housing 22 via a ball joint 26. ing. The rotating rod 25 is slightly movable in the front-rear direction with respect to the ball joint 24 or the ball joint 26.

Although it is not shown in the back of the subject installation plate 23, the fourth
The relay lens, the condenser lens and the infrared reflection filter shown in FIG. 5 and FIG. Further behind these, as shown in FIG. 1, are a light source 2 such as a halogen lamp and a reflector 3.
Are fixedly arranged on the rotating rod 25.

In the above-mentioned configuration, the projection lens 9 can be moved to an arbitrary position within a plane parallel to the external screen by moving the column 21B in the horizontal direction or moving the arm 21C in the vertical direction. Become. At this time, as the lens housing 22 moves, the front half of the rotating rod 25 rotates about the ball joint 24 as a fulcrum, whereby the latter half rotates in the opposite direction. At that time, since the light source 2, the reflector 3, the infrared reflection filter, the condenser lens, the relay lens, the subject 7, the condenser lens and the projection lens 9 are all arranged along the rotating rod 25, the light source 2 and the reflector 3 are separated from each other. The light always passes through the subject 7, is condensed by the projection lens 9, and is further irradiated to the front.

With this configuration, when the projection lens 9 is moved upward in the casing 1 as shown in FIG. 2, for example, the projection lens 9 is moved along the extension line connecting the center of the projection lens 9 and the center of the fixed subject 7. The light source 2 moves naturally and the subject 7
The irradiation light of is incident on the projection lens 9. At this time, since the subject 7 and the screen 40 as the projection surface are orthogonal to the axis L of the projection lens 9, the projection image 7A is an image in which the subject 7 is magnified vertically and horizontally at the same magnification.

Similarly, when the projection lens 9 is moved to the left side in FIG. 1, the light source 2 naturally moves to the opposite side through the fixed subject 7 as shown in FIG. Then, the subject 7 is illuminated. Also in this case, since the subject 7 and the screen 40 are orthogonal to the axis L, the projection image 7A is an image in which the subject 7 is vertically and horizontally enlarged at the same magnification.

In addition to this, even when the projection lens 9 is moved to an arbitrary position, the subject 7 and the screen 40 are always orthogonal to the axis L, and it is possible to obtain a distortion-free projected image 7A.

In the above embodiment, the projection lens 9 is used by using the stand 21.
However, the stand 21 is provided on the light source 2 side to move the light source 2, and the projection lens 9 is made to follow this.
May be moved in the opposite direction. Further, as long as the light source 2 and the projection lens 9 move in opposite directions with the subject 7 as the center, the drive mechanism is not limited to the rotating rod 25, the stand 21, etc., and may be another drive mechanism.

(Effect of the Invention) As described in detail above, according to the present invention, the axis of the projection lens that moves in a plane is always orthogonal to the subject and the external projection plane, and the direction opposite to the projection lens is seen through the subject. Since the projection lens can always collect the light emitted from the light source that moves to, the projection image that is always distorted is formed not only on the direction of the center of the projection device but also on the projection surface located diagonally to the projection device. Can be made to image. Therefore, due to physical restrictions such as the venue, the projection device and the projection surface cannot be at the same height, or the projection device cannot be provided in the center of the audience seat.
Even when the screen cannot be tilted, the projection lens is moved to set the projection surface to any position in the front, bottom, left, and right of the projection device, so that a distortion-free projection image is always formed in front of the venue. be able to.

Therefore, there are less restrictions on the installation location of the projection device, and the degree of freedom in setting up the venue is increased. Further, since the projection lens and the light source can be integrally moved in opposite directions, and a driving means and an operation for individually moving each are unnecessary, the structure can be simple and the operation is not complicated.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention.
FIG. 1 is a perspective view showing the internal structure, FIG. 2 is a side view showing the operation, FIG. 3 is a plan view showing the same operation, and FIGS. 4 and 5 are side views showing a conventional example. 1 ... Casing, 2 ... Light source 3 ... Reflector, 4 ... Infrared reflection filter 5 ... Condenser lens, 6 ... Relay lens 7 ... Subject, 7A ... Projected image 7 '... Slide film, 8 ... … Condensing lens 9 …… Projection lens, 21 …… Stand 22 …… Lens housing, 23 …… Subject mounting plate 24,26 …… Ball joint, 25 …… Rotating rod L …… Axis

Claims (1)

[Scope of utility model registration request] 1. A projection device for illuminating a subject by a light source and enlarging and projecting a projection image of the subject on an external projection surface via a projection lens, wherein the projection lens has an axis of the subject and the projection. It is movable in a plane parallel to the subject and the projection plane in a state orthogonal to the plane, and is arranged on the opposite side of the projection lens via a fixed subject and reverses with the movement of the projection lens. A projection device, wherein irradiation light from the light source moving in any direction can be always condensed by the projection lens.