JPH088002B2 - Electronic light modulation projector - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic light modulation and projecting device, and more specifically, to an instantaneous light used in a stage, a theater, a concert hall, a wedding hall, a television studio, or the like. Can convert the color of
Further, the present invention relates to a light projecting device capable of dimming control.

(Prior Art) Conventionally, in a projector such as a stage, a color filter is used to convert the color of light. That is, as a plurality of color filters inside the housing or on the front surface of the light projecting lens, for example, color filters of cyan (C), magenta (M), yellow (Y), etc. are arranged at right angles to the optical axis. It is provided so that it can be inserted or removed. Then, each color filter operates in conjunction with a motor provided in the housing, and by driving the motor, the color filters are appropriately combined to produce various kinds of light colors. ing. That is, it is a color conversion method using the principle of subtractive color mixing.

Alternatively, it is a color conversion method using the principle of additive color mixing in which color is mixed on the surface to be illuminated by using color filters of red (R), green (G), blue (B), and the like.

Furthermore, when a plurality of color filters are connected in series in the longitudinal direction at regular intervals and the color filters are wound around a winding roll attached to the front surface of the light projecting lens, a motor linked with the winding roll is used. By driving, a desired color of light is produced through various kinds of color filters.

Regarding the dimming control, the voltage is controlled in the power supply circuit to perform the dimming control, or the light amount control means is arranged at a position where the light from the light source passes.

(Problems to be Solved by the Invention) However, in the above-described conventional light projecting device, control of the motor for frequently replacing the color filter is complicated.
In addition, the size of the device is increased because it is necessary to install a motor that drives each color filter.

Furthermore, for color filters connected in series at regular intervals in the longitudinal direction, when these color filters are wound on a take-up roll, the color filters should be placed so that the optical axis is at a right angle to the center of the desired color filter. Accurate stoppage, that is, optimal drive control of the motor, is extremely complicated.

Further, since the conversion speed of the color of light depends on the driving speed of the motor, it is extremely difficult to instantaneously convert the light of a desired color.

Furthermore, a noise for driving and controlling the motor is generated, and in a stage or the like where a large number of spectators are present, this noise is unpopular with surrounding spectators.

Further, regarding the dimming control, the power supply circuit becomes complicated, and when the light amount control means is arranged, the device becomes very large.

(Object of the Invention) The present invention has been made in order to solve such a problem, and rotates a color filter for properly combining a plurality of color filters or connecting a series of color filters at regular intervals. Therefore, without using a motor to drive, the drive control of the motor becomes unnecessary, noise is not generated, the desired color of light is instantly converted, and dimming control can be easily performed.
Another object of the present invention is to provide a light projecting device which can always keep the temperature of the housing constant.

(Means for Solving the Problems) That is, the electronic light modulation and projection device of the present invention includes a light source, a reflecting mirror, a position where the direct light emitted from the light source and the reflected light reflected from the reflecting mirror pass through. A heat ray cut filter, a condenser lens slidably mounted parallel to the optical axis, a light projecting lens for projecting the light condensed by the condenser lens onto an irradiation surface, and the heat ray. In a spotlight in which a light modulator sandwiched between two polarizers is disposed between a cut filter and the light projecting lens, a polarizer rotatable about an optical axis at a predetermined interval on the irradiated side of the light modulator. Is installed, and the color light is converted into color light by selectively controlling the applied voltage to the light modulator, and the polarized light is centered around the optical axis of the polarizer on the irradiated side of the light modulator. It is characterized in that the color light converted light is dimmed by controlling the rotation of the child.

Further, the present invention is characterized in that any one of a halogen lamp, a metal halide lamp, a xenon lamp and a Mercury lamp is preferably provided as a light source.

Further, the present invention is preferably characterized in that a cooling means for cooling the reflecting mirror, the heat ray cut filter or the optical modulator is provided, and the temperature of the housing can be maintained at a predetermined temperature.

(Operation) Hereinafter, description will be given with reference to FIG.

The electro-optical modulation light projecting device of the present invention instantly changes the color of light by applying a voltage between the heat ray cut filter (3) and the light projecting lens front surface part (8) or to the light projecting lens front surface part (8). It has a structure in which at least one set of a light modulator (4) that can be converted into an optical modulator and a rotatable polarizing plate (5) is provided.

Therefore, for example, when the optical modulator (4) and the rotatable polarizing plate (5) are provided between the heat ray cut filter (3) and the condenser lens (6), the following action is exhibited.

First, part of the light emitted from the light source (1) is reflected by visible light by a reflecting mirror or an infrared transmissive reflecting mirror (2) that transmits infrared light and reflects visible light. The visible light reflected and the direct light from the light source (1) are further transmitted through the heat ray cut filter (3) which reflects or removes infrared rays and transmits the infrared rays without absorbing the visible rays. . This visible light becomes incident light that enters the light modulator (4).

Then, as shown in FIG. 2 (a) or FIG. 2 (b), this incident light has a predetermined shape and a predetermined distance between two polarizers A and B whose polarization axes are orthogonal to each other. The light enters a light modulator including a secondary electro-optical element provided with interdigitated electrodes. This secondary electro-optical element has a characteristic that the amount of change in birefringence (ΔN) is proportional to the square of the applied voltage (E). Therefore, when a voltage is applied to the electrodes of the secondary electro-optical element, the amount of light incident on the secondary electro-optical element can be controlled and the color of the light can be changed.

Regarding the control of the light quantity, the operation principle of the light modulator is as follows. Incident light has a vibrating surface in all directions and includes the entire visible range. When this incident light passes through the polarizer A, it is linearly polarized.

Next, when the secondary electro-optical element is not applied, this linearly polarized light is not affected by the plane of polarization of the secondary electro-optical element when passing through the secondary electro-optical element, so that as shown in FIG. 2 (a). Then, the light enters the polarizer B as it is. Since the polarization axis of the polarizer B and the plane of polarization of the linearly polarized incident light are orthogonal to each other, the linearly polarized light that has passed through the secondary electro-optical element is blocked. At this time, the optical modulator is turned off.

On the other hand, when a specific voltage is applied to the optical modulator, birefringence occurs in the secondary electro-optical element, and as shown in FIG. 2 (b), incident light linearly polarized after passing through the polarizer A is secondary. When passing through the electro-optical element, its plane of polarization is rotated by 90 ° and enters the polarizer B. At this time, the polarization axis of the polarizer B coincides with the angle of the plane of polarization of the linearly polarized light that has passed through the secondary electro-optical element, and this linearly polarized light passes through the polarizer B. At this time, the light modulator will exhibit maximum transmittance. The applied voltage showing the maximum transmittance is called the half wavelength voltage of the optical modulator.

Here, when the applied voltage is between zero and a half-wave voltage, the linearly polarized incident light passes through the secondary electro-optical element to become elliptically polarized light having an axis in the same direction as the polarization axis of the polarizer A. When the applied voltage is zero, the diameter of the axis of elliptically polarized light in the direction orthogonal to the polarization axis of the polarizer A becomes zero, and linear polarization having only the component in the same direction as the polarization axis of the polarizer A is obtained. Then, as the applied voltage increases, the diameter of the axis of the elliptically polarized light in the direction orthogonal to the polarization axis of the polarizer A relatively increases with respect to the diameter of the other axis. When the applied voltage is a half wavelength voltage, the elliptically polarized light has a diameter of the axis in the same direction as the polarization axis of the polarizer A becomes zero,
Only the other axis component is formed, and it becomes a linearly polarized light rotated by 90 ° from the polarization axis of the polarizer A.

When the applied voltage is continuously changed from zero to the half-wave voltage in this manner, the two diameters of the elliptically polarized light passing through the secondary electro-optical element are continuously changed. As a result, the vector component in the same direction as the polarization axis direction of the elliptically polarized light polarizer B that has passed through the secondary electro-optical element also changes continuously, and the transmittance of this optical modulator changes continuously. That is, by changing the applied voltage of the optical modulator from zero to a half-wave voltage, a dimming function of continuously changing the amount of incident light transmitted from zero to a maximum value becomes possible.

Next, the operation principle of changing the color of light by the light modulator is as follows.

The light control function of the above-mentioned optical modulator by the secondary electro-optical element has wavelength dependence. Half wavelength voltage is 550nm
The optical modulator shows the voltage at which the maximum transmittance is achieved. Strictly speaking, the transmittance of the optical modulator is slightly deviated from the maximum value with respect to incident light having a wavelength other than 550 nm. However, in the vicinity of the half-wavelength voltage, the difference in transmittance at each wavelength is relatively small, and the color of light hardly appears between the applied voltage of zero and the half-wavelength voltage. That is, FIG. 3 shows the relationship between the applied voltage and the transmittance when three different wavelengths in the light modulator are used as the incident light.

Here, at the half-wavelength voltage P point, since the difference in transmittance between the respective wavelengths is relatively small, all three light colors appear, and the transmitted light becomes close to white light.

When the applied voltage is further increased, the difference in transmittance between wavelengths increases. Next, at point Q, the light of 530 nm is maximally transmitted, but the other lights of 450 nm and 630 nm are hardly transmitted. As a result, at point Q, the transmitted light is 530n.
The wavelength characteristic has a peak near m, and color appears in light. That is, since the incident light transmitted through the polarizer A includes the entire visible region, the spectral transmission characteristic is not flat at a voltage of half a wavelength or longer. Therefore, a color appears in the light transmitted through the light modulator. That is, when the applied voltage is changed, the position of the peak on the spectral characteristic of the light that has passed through the optical modulator changes, and various colors can appear in the transmitted light. Here, if the applied voltage and the color of the transmitted light are made to correspond,
The color of the transmitted light can be controlled by the voltage.

Next, the light of the specific wavelength transmitted through the polarizer B is incident on the rotatable polarizer (5). Then, set the polarizer (5) to 0
By rotating in the range of 90 ° to 90 °, the polarization axis direction of the polarizer (5) also rotates in the range of 0 ° to 90 °. Then, the light transmitted through the light modulator (4) is transmitted through the polarizer (5) as the polarization axis of the polarizer (5) approaches a certain angle θ.

That is, the transmittance of light is increased or decreased through the rotatable polarizer (5).

Therefore, the light of a specific wavelength that is transmitted through the light modulator (4) and is variably colored is dimmed through the polarizing plate (5).

Further, the transmitted light that has passed through the optical modulator (4) passes through a collective lens (6) slidably mounted parallel to the optical axis and a light projecting lens (7) for projecting light onto the illuminated surface. It is possible to project a light beam having an appropriate diameter from the front surface portion (8) of the light projecting lens to the illuminated surface (9).

Further, even when the light modulator (4) and the rotatable polarizing plate (5) are provided between the condenser lens (6) and the light projecting lens (7) or on the light projecting lens front face portion (8), As described above, the same operation as in the case where the optical modulator (4) and the rotatable polarizing plate (5) are provided between the heat ray cut filter (3) and the condenser lens (6) is exhibited.

Further, control of a power source device (not shown) for the light source, a power source device (not shown) for the optical modulator, a rotation driving means (not shown) for the polarizing plate, a sliding means (not shown) for the condenser lens, etc. Alternatively, the control of the means for cooling the reflecting mirror, the heat ray cut filter, the light modulator, etc. is performed by a control device (not shown) based on the lighting technique according to the scene,
Integrated and optimal remote control is possible.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is a light source, and one of a halogen lamp, a metal halide lamp, a xenon lamp and a Mercury lamp, which is a high-intensity light source, is preferable. Reference numeral 2 denotes a reflecting mirror or an infrared transmissive reflecting mirror. Particularly, in the case of an infrared transmissive reflecting mirror, a dielectric having a characteristic of transmitting infrared rays and reflecting only visible light to a substrate made of glass or metal. It is a cold mirror with a body multilayer coating. 3 is
The heat ray cut filter is composed of a plurality of cold filters 3a, 3b, 3c that reflect or remove infrared rays and transmit visible light without absorbing it. In addition, it is preferable that at least one infrared reflecting filter is used as the heat ray cut filter in terms of durability. 4 is
PLZT light modulator. Reference numeral 5 denotes a rotatable polarizing plate. A condenser lens 6 is slidably attached to the housing in parallel with the optical axis. Reference numeral 7 is a light projecting lens. Reference numeral 8 denotes a front surface of the light projecting lens, which is conventionally attached with a color changer device including a plurality of color filters. 9 is a surface to be illuminated. Reference numeral 10 is a blower fan, which is a means for cooling the reflecting mirror, the heat ray cut filter, or the PLZT light modulator. 11 is a housing.

FIG. 2 (a) shows a PLZT optical modulator including a PLZT element in which electrodes having a predetermined shape and a predetermined interval are provided between two polarizers A and B whose polarization axes are orthogonal to each other, and the PLZT optical modulator. It is a principle diagram of an OFF state of a rotatable polarizing plate arranged on the irradiated side.

FIG. 2 (b) shows a PLZT optical modulator including a PLZT element in which electrodes having a predetermined shape and a predetermined interval are provided between two polarizers A and B whose polarization axes are orthogonal to each other, and this PLZT.
FIG. 8 is a principle diagram of an ON state of a rotatable polarizing plate arranged on the irradiated side of the optical modulator.

The material of this PLZT element is transparent ferroelectric ceramics [lead zirconate (PbZrO ₃ ) and lead titanate (PbTi
O ₃ ) solid solution with lanthanum (La) added (Pb, L
a) (Zr, Ti) O ₃ system].

Further, in this embodiment, PLZT was used as the translucent ferroelectric substance having the secondary electro-optical effect, but as the substance showing the similar secondary electro-optical effect, for example, (Pb, La) (Zr, Nb )
O ₃ system (hereinafter referred to as PLZN) or (Pb, Bi) (Zr, T
i) Similar effects can be expected by using O ₃ system (hereinafter referred to as PBZT).

Further, as the material of the polarizer, for example, a thin plate of polyvinyl alcohol is stretched in one direction while being heated so that molecules are aligned in a certain direction and iodine is impregnated therein. FIG. 3 is a diagram showing the relationship between the applied voltage of the PLZT optical modulator and the wavelength of light. It shows how the peaks of the wavelength are separated and changed by applying a predetermined voltage. is there.

FIG. 4 shows the relationship between the wavelength and the transmittance of the PLZT light modulator. The transmittance becomes maximum at a specific wavelength. That is, light having a specific wavelength is selectively transmitted.
Therefore, it shows that it can be used as a color filter.

FIG. 5 (a) is a plan view of an iris, which is a conventional light amount control means. This is made by stacking a plurality of light-shielding plates of a predetermined shape, and the amount of passing light can be controlled by changing the aperture.

FIG. 5B is a plan view of another dimming control panel, which is another conventional light amount control means. In this method, one or more circles having different radii are arranged concentrically and the disc is rotated to control the amount of light passing therethrough.

FIG. 6 shows another embodiment of the present invention, in which a blower fan is provided as means for cooling the reflecting mirror, heat ray cut filter or PLZT optical modulator. A heat sink or a heat pipe may be used as a cooling means.

7 (a), (b), and (c) are experimental data of the embodiment of the present invention shown in FIG. 1 and show the spectral transmission characteristics of the PLZT optical modulator at each applied voltage. , As transmitted through the PLZT optical modulator. FIG. 7 (a) is a plot of the relationship between wavelength and transmittance for each applied voltage of 125V to 375V. FIG. 7 (b) is a plot of the relationship between wavelength and transmittance for each applied voltage of 375V to 575V.
FIG. 7 (c) is a plot of the relationship between wavelength and transmittance for each applied voltage of 625V to 775V.

That is, it was proved that the three parameters of voltage (v), wavelength (nm), and transmittance (t) changed in relation to each other. Select a specific voltage from this data and use PLZT
When applied to the device, the light could be variably colored, and when the polarizer was then rotated, the light could be dimmed.

(Effects of the Invention) The electro-optical modulation translucent device of the present invention includes a light source, a reflecting mirror,
With the heat ray cut filter arranged at a position where the direct light emitted from the light source and the reflected light reflected from the reflecting mirror pass through, a condenser lens slidably mounted parallel to the optical axis, and this condenser lens In a light projecting device having a light projecting lens for projecting condensed light onto a surface to be illuminated, and a light projecting lens front surface portion, between the heat ray cut filter and the light projecting lens front surface portion, or the light projecting lens front surface. At least one set of a light modulator and a rotatable polarizing plate is provided on the irradiated side of the light modulator at a predetermined interval.

Therefore, the light emitted from the light source is reflected by the reflecting mirror or the infrared transmissive reflecting mirror, and then passes through the heat ray cut filter to reflect or remove infrared rays, and further visible light is transmitted.

This visible light becomes incident light that enters the light modulator, and when this incident light passes through the light modulator that instantly converts the color of light by applying a voltage,
By applying a predetermined voltage to the electrodes of the light modulator, the incident light that has entered the light modulator has the color of the light of the wavelength corresponding to the applied voltage value, which is instantly converted into the desired light color by birefringence. To penetrate.

Next, the light of the specific wavelength that has passed through the polarizer B is incident on the rotatable polarizer. By rotating the polarizer in the range of 0 ° to 90 °, the polarization axis direction of the polarizer also rotates in the range of 0 ° to 90 °. Then, the light transmitted through the light modulator is transmitted through the polarizer as the polarization axis of the polarizer approaches a certain angle θ.

That is, the transmittance of light is increased or decreased through the rotatable polarizer.

Therefore, the light of a specific wavelength that has been variably colored by passing through the light modulator is dimmed through the polarizer.

Furthermore, the transmitted light transmitted from the optical modulator passes through the condenser lens slidably mounted parallel to the optical axis and the light projecting lens, so that the front surface of the light projecting lens has an appropriate aperture on the illuminated surface. A light flux can be projected.

Therefore, without combining a plurality of filters appropriately, or using a motor that rotates a series of connected filters, drive control of the motor is unnecessary, noise is not generated, and the desired color of light is instantly generated. In addition, the dimming control can be performed, and the temperature of the housing can be always kept constant. Furthermore, the device can be made lighter, vibration does not occur, and the operating temperature is -30 ℃
Since a wide range of + 80 ° C is sufficient, there was a side effect that the design was extremely easy.

[Brief description of drawings]

FIG. 1 is a side sectional view of an embodiment of the present invention, FIG. 2 (a) is a principle view of the OFF state of a PLZT optical modulator and a polarizer, and FIG. 2 (b) is a PLZT optical modulator and a polarized light. FIG. 3 is a diagram showing the relationship between the applied voltage of the PLZT optical modulator and the light wavelength, FIG. 4 is a diagram showing the relationship between the wavelength and the transmittance, and FIG. 5 (a) ) Is a front view of an iris by a conventional light amount control means, FIG. 5 (b) is a front view of a dimming control panel by another conventional light amount control means, and FIG. 6 is
FIG. 8 is a side sectional view showing a blower fan for cooling the PLZT optical modulator according to another embodiment of the present invention. 7 (a), (b), and (c) are spectral transmission characteristic diagrams based on experimental data. 1 ... Light source, 2 ... Reflecting mirror, 3 ... Heat ray cut filter, 4 ... PLZT light modulator, 5 ... Polarizing plate, 6 ... Condensing lens, 7 ... Projecting lens, 8 ... Projecting light Front of lens, 9 ... Irradiated surface, 10 ... Blower fan, 11 ... Housing.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Hayashi 1285 Musashino, Oi-cho, Iruma-gun, Saitama Within Artsais Co., Ltd. Saitama factory (72) Inventor Kazumi Ishii 1285 Musashino, Oi-cho, Iruma-gun, Saitama RDS Saitama Co., Ltd. Factory (72) Inventor Kenichi Suzuki 1285 Musashino, Oi-cho, Iruma-gun, Saitama RDS Saitama Factory (56) References JP-A-60-28103 (JP, A) JP-A-60-97502 (JP, A) ) JP-A-55-1065 (JP, A) JP-A-61-74201 (JP, A) JP-A-61-161602 (JP, A) Actual development 62-57302 (JP, U) Actual development 62- 24409 (JP, U) Actual Open Sho 53-123888 (JP, U) Actual Open Sho 54-101886 (JP, U) Actual Open Sho 59-164102 (JP, U) Actual Open Sho 59-115508 (JP, U) Actually open 60-17506 ( P, U) JitsuHiraku Akira 57-130801 (JP, U)

Claims (3)

[Claims] 1. A light source, a reflecting mirror, a heat ray cut filter arranged at a position through which the direct light emitted from the light source and the reflected light reflected from the reflecting mirror pass, and slidably mounted parallel to the optical axis. Between the heat ray cut filter and the light projecting lens, and a light projecting lens for projecting the light collected by the light collecting lens onto the irradiation surface. In the spotlight in which the optical modulator is arranged, a rotatable polarizer is installed on the optical axis at a predetermined interval on the irradiated side of the optical modulator, and by selectively controlling the applied voltage to the optical modulator. Color light is converted into color light, and the color light converted light is dimmed by controlling rotation of the polarizer around the optical axis of the polarizer on the irradiated side of the light modulator. An electronic light modulation light projecting device. 2. The electronic light modulation and projection apparatus according to claim 1, wherein any one of a halogen lamp, a metal halide lamp, a xenon lamp and a Mercury lamp is provided as a light source. 3. A reflecting mirror, a heat ray cut filter or a cooling means for cooling the light modulator is provided to keep the temperature of the housing at a predetermined temperature. 2. The electronic light modulation and projection device described in.