JP2904690B2 - Hologram exposure method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for producing a plurality of identical holograms, such as a high mount stop lamp or a turn signal indicator for a vehicle, a display of a show window, and the like.

[0002]

2. Description of the Related Art A hologram is provided on a rear window glass as a high mount stop lamp for an automobile.
A display device that introduces light from a light source through a prism, irradiates a hologram while totally reflecting the light in a window glass, and diffracts the light backward has been proposed in Japanese Patent Application Laid-Open No. Hei 4-228329. Since the hologram used has an incident angle of one laser beam exceeding the critical angle at the time of exposure, it is necessary to irradiate the dry plate through a prism.

In Japanese Patent Application Laid-Open No. 4-228329, the exposure method is to expose a cylindrical lens array away from the dry plate while fixing the dry plate and the prism.
The holograms to be formed may interfere with adjacent holograms, and a hologram non-recording portion is likely to occur between holograms. In addition, in order to produce holograms of the same quality, both the object light and the reference light are parallel light. Therefore, a concave mirror having a large outer diameter must be prepared, and the optical system becomes expensive.

In addition, as an apparatus for exposing a hologram lens array without using a prism, the present applicant has proposed an apparatus for driving a photosensitive material (dry plate) in the same plane as Japanese Patent Application Laid-Open No. 4-245286. When exposure is performed in this way when exposing using a prism, as shown in FIG. 5, when the dry plate 1 and the prism 2 are moved in parallel from the solid line to the dotted line, one center line of the laser beam is shifted. The hologram forming portion is shifted from the center of the laser beam from two directions, and the intersection of the center lines B ₁ and B ₂ is shifted from the top of the dry plate and formed in the front or the back. There is a drawback that the hologram becomes unrecorded and a hologram unrecorded portion is formed.

The present invention has been made in view of the above points, and has as its object to provide an exposure method and an exposure apparatus suitable for producing a plurality of identical holograms on one photosensitive material. .

[0006]

One of the methods of the present invention is to irradiate a laser beam from two specific directions to a dry plate through a prism to produce a plurality of identical holograms on the dry plate. The method for exposing a hologram, wherein the dry plate and the prism are driven integrally so that an intersection point where the center lines of the laser beams from the two directions intersect is formed on the dry plate. An apparatus for irradiating laser beams from two specific directions to a dry plate through a prism to produce a plurality of identical holograms on the dry plate, wherein the dry plate and the prism are parallel to the dry plate surface. In addition to a dry plate drive comprising an X-axis drive which is driven in the horizontal direction, a Z-axis drive which is movable in the vertical direction parallel to the plate surface and a Y-axis drive which is movable in the direction perpendicular to the plate surface, Storage means for storing a shift amount from the dry plate at the intersection of the laser beam from the direction, characterized in that a controller for outputting a movement amount corresponding to the deviation amount to the drive apparatus so as to at least provided.

Another aspect of the apparatus according to the present invention is that the plate is driven in the same plane while the prism is fixed so that the intersection of the center lines of the laser beams from the two directions is formed on the plate. for so to, a holder for fixing the prism, characterized in that the said dry plates such that at least comprises a driving device for driving at least the vertical and horizontal directions in the same plane.

[0008]

The present invention comprises at least storage means for storing the amount of deviation of the intersection of laser beams from two directions from the dry plate, and a controller for outputting to the drive unit a displacement corresponding to the amount of deviation. The hologram array having the same characteristics can be automatically and easily manufactured by integrally driving the dry plate and the prism so that the intersection point where the center lines of the laser beams from the directions intersect is formed on the dry plate.

Alternatively, a hologram array can be easily and automatically produced by providing a driving device for driving the dry plate at least vertically and horizontally in the same plane while the prism is fixed by the holder. Can be.

In this case, not only the optical system such as a laser oscillator, a beam splitter, a reflecting mirror, and a convex lens but also the prism may be fixed, and it is not necessary to perform complicated setting of the optical system each time. The hologram array having completely the same characteristics can be formed only by driving the hologram in the horizontal and vertical directions in the same plane as the surface of the dry plate.

In this case, the index matching liquid to be filled between the dry plate and the prism is volatile even when a volatile xylene or the like is used. Since there is a possibility that air may enter between the dry plate and the prism, it is only necessary to provide a device for dropping the index matching liquid on the prism and a receiving tray for receiving the dripping liquid. In the case where is used, it may be applied over a wide area and thickly in a portion in contact with the dry plate of the prism.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a main part showing an apparatus for producing a transmission type hologram sheet in Example 1 of the present invention, FIG. 2 is a perspective view of an essential part showing an apparatus for producing a reflection type hologram sheet in Example 2, and FIG. FIG. 4 is a front view of a main part showing a hologram, FIG. 4 is a plan view of a main part for explaining hologram production accompanying movement of a dry plate and a prism in Embodiment 1, and FIG. It is a principal part top view for performing.

Embodiment 1 Referring to FIGS. 1 and 3, an apparatus for driving a drying plate 1 and a prism 2 integrally to expose a plurality of transmission holograms will be described.

[0014] 3-axis drive unit 3 is movable Z-axis driving device movable X-axis drive unit 3 _X direction perpendicular to the horizontal direction the same surface as the surface dry plate 1 3 _Z and dry plate surface A consisting movable Y-axis drive unit 3 _Y in a horizontal direction to a vertical direction.

The three-axis driving device 3 includes a laser oscillator 4, a reflecting mirror 5, a shutter 6, a beam splitter 7, a reflecting mirror 8, a reflecting mirror 9, a microscope objective lens 10, a pinhole 11, a convex lens 12, and a reflecting mirror 13. , Microscope objective lens 14, pinhole 15, device 1 for driving microscope objective lens 14 and pinhole 15 in parallel with the laser beam
Set it on the vibration isolator 17 together with 6. Anti-vibration table 17
Out of the system, control devices such as a stage controller 18, a stage controller 19, a personal computer 20, and a shutter controller 21 are provided.

Next, the operation will be described. For example, a dry plate 1 coated with polyethylene terephthalate or the like as a photosensitive material using dichromate gelatin or the like is fixed together with the prism 2 via an index matching liquid such as xylene.
After setting each optical device so that laser light from two directions is incident on the dry plate 1 at a predetermined angle, a signal is output from the personal computer 20 to the shutter 6 via the shutter controller 21, and the shutter 6 is set to the predetermined angle. When opened, the laser light emitted from the laser oscillator 4 changes its direction by a reflecting mirror 5 and is split into two by a beam splitter 7, one of which is a reflecting mirror 8, a reflecting mirror 9, a microscope objective lens 10, a pinhole 11, and a convex lens. 12, a part H of the dry plate 1 as a plane wave via a masking plate (not shown) and a prism 2 and the other as a spherical wave via a reflector 13, a microscope objective lens 14, a pinhole 15, a masking plate (not shown) and a prism 2 Irradiation is performed on ₁₁ portions, and interference fringes are formed and recorded.

At the same time, a signal is output from the personal computer 20 to the shutter 6 via the shutter controller 21, the shutter is closed, the laser light from the laser oscillator 4 is cut off, and immediately thereafter, the personal computer 20 transmits the signal from the personal computer 20 via the stage controller 18. A signal is output to the three-axis driving device 3 to drive the Z-axis driving device _3Z to raise the dry plate 1 and the prism 2 integrally by one hologram.

After a lapse of a predetermined time from the completion of driving, the shutter controller 2 is again operated from the personal computer 20.
Open the shutter issues a signal to the shutter 6 via the 1, laser light from two directions the interference fringe at this portion is irradiated predetermined time H ₂₁ moiety formed, is recorded.

Hereinafter, interference fringes are formed up to H _m1 by the same method. Next, a signal is output from the personal computer 20 to the three-axis driving device 3 via the stage controller 18 to drive the Z-axis driving device 3 _Z , while lowering the dry plate 1 and the prism 2 together and returning to the initial position, By driving the X-axis driving device 3 _X and the Y-axis driving device 3 _Y , the dry plate 1 and the prism 2 are moved horizontally by one hologram in the X-axis direction and the Y-axis direction, and almost simultaneously from the personal computer 20 via the stage controller 19. Then, a signal is output to a device 16 which is driven in parallel with the laser beam to drive the microscope objective lens 14 and the pinhole 15 integrally.

After a lapse of a predetermined time from the completion of driving, the shutter controller 2 is again operated from the personal computer 20.
Open the shutter issues a signal to the shutter 6 via the 1, 2 laser beam from the direction is emitted a predetermined time H ₁₂ moiety interference fringes this part forms, it is recorded.

Hereinafter, H₁₁To H_m1H in the same way as
_m2After forming and recording interference fringes up to the portion,_m1To H₁₂To
H is moved in the same manner as when the dry plate 1 and the prism 2 are moved.₁₃
An interference fringe is formed in a portion,_m3Interference fringes up to
Repeat steps like _mnAn interference fringe is formed up to.

Specifically, the pitch of the number of holograms is 6 mm wide and 5 mm long, and the angle of the cut surface of the prism is 30 mm.
°, height 65mm, upper and lower sides each 130mm
And 100 mm, the incident angle of the beam B ₁ is 10.0 °,
Beam B ₂ the amount of movement of the dry plate and the prism when the angle of incidence was set 10.0 ° -5 per one X-axis direction hologram.
046Mm, Y-axis direction is 0.2622mm movement, preferably a microscope objective lens 14 and a pinhole 15 is better that 0.2662mm moved into the beam B ₂ direction, vertical direction, that hologram one per 6 in the Z-axis direction, 0
mm. The shift amount at this time is -0.046 mm (-5.046 mm-(-5 mm)) in the X-axis direction and 0.2622 mm in the Y-axis direction per hologram.

As shown in FIG. 4, when the hologram pitch is set to L (mm), the dry plate 1 and the prism 2 indicated by solid lines are moved to the positions indicated by the dotted lines. When the center of the hologram P ′ (X ′, Y ′) is recorded by shifting the center of the hologram P (X, Y) by one pitch in the horizontal direction (X axis), each reference point P ₀ is recorded.
And the plane coordinates of P ₀ ′ are known (X ₀ , Y ₀ ) and unknown (X ₀ ′, Y ₀ ′), then X ′ = X ₀ ′ −L + (X
−X ₀ ) (1) holds, and the beam B ₁ and the beam B ₂ before movement are satisfied.
Since the linear equations are known, the moved beam B
₁ ′ and beam B ₂ ′ are also X ₀ , Y ₀ , X ₀ ′, Y ₀ ′, Can be expressed as a linear expression using
This solution satisfies X = X ′, Y = Y ′ and X ₀ ′, Y ₀ ′, X ′, Y ′ so as to satisfy the above equation (1).
Is determined, the amount of movement of the dry plate and the prism is X ₀ ′ −X _{0 in} the X-axis direction, Y ₀ ′ −Y ₀ in the Y-axis direction, and the amount of displacement is X′−X, Y in the X-axis direction. Y′−Y in the axial direction.

The dry plate on which a plurality of interference fringes are formed is removed from the holder and developed by an ordinary method to obtain a hologram sheet having a plurality of holograms.
The wavelength of the laser beam and the angle of incidence of the laser beam from the two directions with respect to the hologram master are determined in consideration of the conditions during reproduction (the position and type of the light source, the position of the human eye) and the change in the thickness of the photosensitive material. It can be set by Bragg's formula.

Embodiment 2 With the prism 2 fixed to the mounting table 22, the dry plate 1 is held by a holder 23 via a nonvolatile index matching liquid such as a microscope immersion oil (manufactured by Nikon), and is held in the same plane. An apparatus for driving and exposing a plurality of reflection holograms will be exemplified.

The two-axis driving device 3 is the same surface as the surface of the dry plate 1 and is horizontally movable. The X-axis driving device 3 _X and the dry plate surface are in the same plane and are vertically movable. consisting axis drive unit 3 _Z.

[0027] Such two-axis driving unit 3 to the laser oscillator 4, the reflecting mirror 5, a shutter 6, the beam splitter 7, a reflecting mirror 8, the reflecting mirror 9, the microscope objective lens 10, pinhole 11, the reflecting mirror 13, the microscope objective The lens 14 and the pinhole 15 are set on the vibration isolator 17. A stage controller 18, a personal computer 20, a shutter controller 2
A control device such as 1 is provided.

Next, the operation will be described. For example, after holding a dry plate 1 coated with polyethylene terephthalate or the like using a photopolymer or the like as a photosensitive material in a holder 23, after setting each optical device such that laser light from two directions is incident on the dry plate 1 at a predetermined angle. , Personal computer 20 to shutter controller 2
1, a signal is output to the shutter 6 and the shutter 6
Is opened for a predetermined time, the laser light emitted from the laser oscillator 4 changes its direction by a reflecting mirror 5 and is split into two by a beam splitter 7, one of which is a reflecting mirror 8, a reflecting mirror 9, a microscope objective lens 10, and a pinhole 11 , as a spherical wave via a masking plate (not shown) and the other reflecting mirror 13, a microscope objective lens 14, pinhole 15, a masking plate (not shown), through the prism 2 in a part H ₁₁ portion of each dry plate 1 as a spherical wave Irradiation forms and records interference fringes.
At the same time, a signal is output from the personal computer 20 to the shutter 6 via the shutter controller 21, the shutter is closed, the laser beam from the laser oscillator 4 is shut off, and immediately thereafter, the two-axis drive is performed from the personal computer 20 via the stage controller 18. signal is issued to the device 3 to drive the Z-axis drive unit 3 _Z a dry plate 1 is raised one minute hologram.

After a lapse of a predetermined time from the completion of the driving, the shutter controller 2 is again operated from the personal computer 20.
Open the shutter issues a signal to the shutter 6 via the 1, laser light from two directions the interference fringe at this portion is irradiated predetermined time H ₂₁ moiety formed, is recorded.

Hereinafter, interference fringes are formed up to H _m1 by the same method. Next, a signal is output from the personal computer 20 to the two-axis driving device 3 via the stage controller 18 to drive the Z-axis driving device 3 _Z , while lowering the dry plate 1 to return to the initial position, _X is driven to move the plate 1 horizontally by one hologram in the X-axis direction.

After a lapse of a predetermined time from the completion of the driving, the shutter controller 2 is again operated from the personal computer 20.
Open the shutter issues a signal to the shutter 6 via the 1, 2 laser beam from the direction is emitted a predetermined time H ₁₂ moiety interference fringes this part forms, it is recorded.

Hereinafter, H ₁₁ is set in the same manner as H ₁₁ to H _m1.
forming interference fringes to _m2 portion, after recording, forming interference fringes H ₁₃ portion in the same manner as the H _m1 of moving the dry plate 1 to H _12, below, form the interference fringes to H _m3, this By repeating such a procedure, interference fringes are formed up to _Hmn .

Although the preferred embodiments have been described above, the present invention is not limited to these embodiments, and various applications are possible. In this embodiment, the array type hologram sheet used for the high-mount stop lamp has been described. However, the same type of hologram sheet can be simultaneously used by separating and using a plurality of holograms. Can be obtained.

The laser light applied to the photosensitive material from two directions is
Although the description has been made of the example in which exposure is performed using a spherical wave and a plane wave or a spherical wave and a spherical wave, exposure may be performed by adding a convex lens and using both laser beams as a plane wave.

Regarding the optical device, a pinhole (spatial filter) has an effect of removing a high-order diffraction pattern of a laser beam, and because of dust and scratches attached to a lens, the spread light is diffracted by those. It is better to provide the interference fringes so as to eliminate the effect of forming unnecessary interference fringes on the subject and obtain a clear wave.

Further, a masking plate which perforates the center and shields the periphery is not necessarily required. However, since the light intensity and the like are not uniform between the center and the outside of the light beam, the outside light is blocked. It is better to provide it so that uniform light can be emitted.
Further, by changing the shape of the light transmitting portion of the masking plate, holograms having various shapes such as a circle, an ellipse, a square, and a rectangle can be obtained.

As for the photosensitive material, dichromated gelatin,
In addition to the photopolymer, a silver halide photosensitive material, various photoresists, and the like may be appropriately selected and used. Further, depending on the photosensitive material, the thickness of the hologram can be swelled or shrunk by heat or chemical treatment after exposure. By utilizing this characteristic, it is also possible to calculate and expose appropriate f ₁ and f ₂ in advance so that the hologram finally has the optimum focal length as described in this specification. Further, the hologram exposed by the spherical wave can be swollen or shrunk to have the same interference fringe as that obtained when the hologram is exposed by an arbitrary aspherical wave.

The hologram obtained by the present invention is suitable not only as a high-mount stop lamp but also as a turn signal indicator for automobiles, and may be displayed in various colors. It can be applied to architectural windows, partitions, etc.

[0039]

According to the method and apparatus for producing a hologram of the present invention, a large number of holograms having the same characteristics can be produced quickly, easily and automatically without the necessity of setting a complicated optical apparatus each time. Is what you can do.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part showing an apparatus for manufacturing a transmission type hologram sheet in Example 1 of the present invention.

FIG. 2 is a perspective view of a main part showing an apparatus for manufacturing a reflection type hologram sheet in Embodiment 2 of the present invention.

FIG. 3 is a main part front view showing a plurality of holograms.

FIG. 4 is a main part plan view for explaining hologram production accompanying movement of a dry plate and a prism in the first embodiment of the present invention.

FIG. 5 is a plan view of a main part for describing a problem when the dry plate and the prism are moved in parallel.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Dry plate 2 Prism 3 3 axis drive or 2 axis drive 3 _X X axis drive 3 _Y Y axis drive 3 _Z Z axis drive 4 Laser oscillator

Claims (3)

(57) [Claims] 1. A hologram exposing method for irradiating laser beams from two specific directions to a dry plate through a prism to produce a plurality of identical holograms on the dry plate.
A method for exposing a hologram, wherein the dry plate and the prism are integrally driven such that an intersection of the center lines of the laser beams from the two directions is formed on the dry plate. 2. An apparatus for producing a plurality of identical holograms on a dry plate by irradiating laser light from two specific directions to the dry plate through a prism, wherein the dry plate and the prism are arranged in parallel with the surface of the dry plate. In addition to a dry plate drive including an X-axis drive that is driven in the horizontal direction, a Z-axis drive that is movable in the vertical direction parallel to the plate surface, and a Y-axis drive that is movable in the direction perpendicular to the plate surface, 2 A hologram characterized by comprising at least a storage unit for storing a shift amount of the intersection of the laser beam from the direction from the dry plate from the dry plate, and a controller for outputting a movement amount according to the shift amount to the driving device. Exposure equipment. 3. An apparatus for irradiating laser beams from two specific directions to a dry plate through prisms to produce a plurality of identical holograms on the dry plate, comprising: a holder for fixing a prism; An exposure apparatus for a hologram, comprising at least a driving device for driving at least vertically and horizontally in the same plane.