JPS6113771A - Line scanner using plzt - Google Patents

Abstract

PURPOSE:To eliminate the horizontal flyback time and to perform a scan with high optical efficiency by impressing the voltage accordant with a video signal to plural counter electrodes provided centering on a belt-shaped line and modulating the incident light given to the dot area. CONSTITUTION:Electrodes 3 (3a, 3b) produce the lateral mode electric field to an artificial ceramic polycrystalline substance PLZT1 and are wired and connected to plural pairs of switches 6a and 6b. The switches 6b of the row direction are always closed and the switches 6a of the column direction are controlled to open the electrodes 3 successively from an end side according to a video signal. Thus the light given from a light source is transmitted through the PLZT1 and reflected by a reflecting plate 5 to be transmitted again through the PLZT1. The PLZT1 polarizes only the transmitted light having a vibrating surface at a prescribed angle when the voltage is impressed to the electrodes 3 with addition of an electric field vertical to the transmitted light. Thus the intensity of the transmitting light can be changed with use of a PLZT polarizing plate and an analyzer. Then the light given from the light source can be modulated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a line scanner using PLZT.

<Prior Art> High-resolution color TV projectors or optical scanning VTRs require horizontal scanning means, and conventionally a rotating mirror or a pure optical crystal such as DKDP, LiNbO3, etc. has been used.

However, horizontal scanning using a rotating mirror requires retrace time, making real-time processing difficult, and when using a rotating mirror, such as an air bearing type rotating mirror that rotates at tens of thousands of revolutions per minute, it requires a precise mechanical structure and a large amount of power for driving. It cost.

Furthermore, when a pure optical crystal is used, a vacuum container and a cooling device are required in the electron beam method, and there are further obstacles such as the complexity of processing the crystal in the mosaic transverse electric field control method.

It is not suitable for mass production.

Additionally, there are some methods that use an acoustic optical deflector (ultrasonic deflector) or a liquid crystal element, but it is difficult to obtain high resolution and high response speed when scanning with a short retrace time. .

OBJECTS OF THE INVENTION The present invention was provided in order to eliminate the drawbacks listed in -h. It is about providing.

■Another objective is to provide a power-saving and light-efficient line scanner.

-Another objective is to provide a line scanner with a large contrast ratio and high resolution, especially a line scanner with good color resolution.

Another object is to provide a line scanner that can be mass-produced as single and double elements.

Structure of the Present Invention The present invention comprises an rPLZT, a plurality of opposing electrodes arranged in pairs across a strip line set to a constant width on one surface of the P'LZT, and and a dot area formed on the line with the width of the strip line and the width of the counter electrode as sides, and a video signal 1 is transmitted to the counter electrode.
A PLZT characterized in that the light incident on the dot area can be modulated by applying a voltage according to the video signal and applying a transverse mode electric field to the dot area according to the video signal.
A line scanner using

<Example> Next, the present invention will be explained in more detail according to an example shown in the drawings.

In FIG. 1, (1) is PLZT. PLZT is
(Pb, La) (Zr, Ti)0. '2 ceramics, which is a solid solution of PbTi0 and PbZr0.
, Ti)03 to which several mol% of La is added is an artificial ceramic polycrystal having electro-optical properties. (2) is an insulating layer of silicon oxide (Si(h)), and (3) is a gold (A
u), an electrode made of aluminum (AI), etc., and the PLZT (1)
A strip line (50
) are arranged in pairs with the two sides in between. (4) is a transparent layer of aluminum oxide (AlO2), (5) is an aluminum reflector, and (30) is a PLZT layer between the electrodes (3a) and (3b).
This is a dot area formed on the top, and is formed in a rectangular shape whose sides are the width of the line and the width of the electrode.

The electrode (3) provides a transverse mode electric field to the I'LZT (1), and is wired to switches (6a) and (8b) arranged in eg 1024 pairs on one side of the PLZT (1). In order to form one scanning line according to the video signal, the row direction switch (817) is normally closed and the column direction switch (6a) is controlled to connect the electrodes (3).
are opened sequentially from one end according to the video signal,
Allows light from a light source to pass through. The light from the light source (11) is P
After passing through LZT (1), it is reflected by 1 reflection plate (5),
It passes through p L Z T (1) again.

Therefore, P L Z T (1) is because when a voltage is applied to the electrode (3) and an electric field (transverse mode electric field) perpendicular to the passing light is applied, only the transmitted light with a vibration plane at a predetermined angle is polarized. ,
By using a PLZT polarizer and an analyzer, the intensity of the passing light can be varied and the light from the light source (11) can be modulated.

FIG. 4 shows a principle diagram of an apparatus for projecting an image onto a large screen as an application example of a system using such a line scanner.

(11) is a light source, which uses a xenon lamp, a halogen lamp, a three-color laser light source, or the like.

(12) is the beam 1, a condensing lens which is a magnifier, (13) is a polarizing plate, (14) is a square aperture diaphragm, (15) is a condensing lens which is a horizontal/linear illuminator, and (16) is a beam splitter.
1 (17a) is a red reflective dichroic mirror, (+7
b) is a blue reflection gicchroic mirror, (18) is a line scanner, (18) is an analyzer, (20) is a collimating lens, (21) is a sub vertical polarizer, (22) is a 111 direct polarizer (23) is a high-resolution reduction lens, (2A,)
is a projection lens, and (25) is a screen.

The normal light generated from the light source (11) passes through the condensing lens (12) and is polarized by the polarizing plate (13).
After the light is converted into a band of a predetermined width and length by a square 1" diameter diaphragm (14) and a condensing lens (15), it is converted into a band of light with a predetermined width and length by a beam splitter (16) and a red reflective dichroic mirror (17).
It is bent in the direction of a). Next, the red light (R) component is separated by a gicroic mirror (17a), and the entire length of the band-shaped light is divided into a predetermined number of dots (3G)... by a line scanner (18a) for successful red modulation. The beam is scanned sequentially from one end and modulated and reflected. The blue (B) component is a blue reflective guichroic mirror (17b).
) for blue component modulation using a line scanner (
18b), and the green (G) component is scanned, modulated, and reflected by a line scanner (18c) for modulating the green (G) component. Therefore, the modulation by the line scanners (18a), (18b), and (18c) is as described above (the direction of polarization is changed according to the voltage applied to the PLZT, and as a result, each modulated color tone is The component polarized light becomes return light and passes straight through the beam splitter (1B), and only the polarized light in a certain direction is passed by the analyzer (19), so the line scanners (18a), (18b), The light is emitted with an intensity corresponding to the modulation by (18c).Furthermore, it passes through the collimating lens (20), and is vertically polarized by the auxiliary vertical polarizer (21) and +1 (anti-scratch optical device (22)). Furthermore, the light passes through a high-resolution reduction lens (23), is condensed, and is projected onto a screen (25) by a projection lens (24).

Then, the line scanner (18) performs horizontal scanning, and the sub-vertical polarizer (21) and vertical changer (22)
performs vertical scanning and projects an image onto the screen (25).

As mentioned above, the line scanners (18a), (18b), and (18c) modulate the light from the light source (11) according to the video electric signal. Screen the image (
25).

Furthermore, the line scanner according to the present invention can be applied not only to the above-mentioned projection onto the screen but also to writing to and reading from a magnetic tape/disc.

Furthermore, PL Z in this line scanner (18)
T (1) is a ferroelectric material, and the polarized state generated by the application of voltage remains even when the voltage is reduced to zero, so it has a memory effect and can be applied as an IH memory. This memory time is about 1 to 2 minutes, and it can be erased immediately by applying a voltage of opposite polarity.

Effects of the Invention> According to the invention, it is possible to eliminate the retrace time of horizontal scanning, which was considered to be a difficult point in the prior art, and since reading and video dots completely match, information blanks do not occur. It can be visualized without any problems. In particular, optical scanning VTRs are capable of continuous real-time signal processing (recording and reproduction) without information defects. Therefore, since the original optical scanning only needs to be used for vertically polarized light, the drawbacks of the conventional XY scanner can be overcome by combining it with an appropriate low-speed, high-resolution optical scanner to form an XY scanner.

That is, unlike conventional pure ceramic polycrystals, it can be mass-produced, and unlike the case of using a rotating mirror, power consumption can be saved. Furthermore, the naturally polarized light can be used with high optical efficiency due to the memory effect and modulation effect of I'LZT.

For example, Green 555nmlW light has a light absorption of 680 lumens, so an IKW xenon lamp has a light absorption of 200 lumens.
Since it is possible to obtain a minimum light output of 1.5 lumen, if only complete visible light is illuminated through a cold mirror, it can be processed and mass-produced as a small MSIC without thermal damage.

[Brief explanation of the drawing]

FIG. 1 is a partially omitted enlarged plan view showing an embodiment of a line scanner according to the present invention, and FIG. 2 is an II--
FIG. 3 is an explanatory diagram showing electrode wiring, and FIG. 4 is an explanatory diagram of an optical system showing an embodiment applied to a color VTR projector. (1)...PLZT, (2)...Insulating layer, (3) (3a) (3b)...Electrode, (30
)...Dot area (5)...Reflector,

Claims (1)

[Claims] 1. A PLZT, a plurality of opposing electrodes arranged in pairs across a strip line set to a constant width on one surface of the PLZT, and a width of the strip line and a width of the strip line. a dot area formed on the line with the width of the opposing electrode as a side; and a voltage corresponding to a video signal is applied to the opposing electrode to modulate incident light to the dot area. A line scanner using PLZT characterized by the following. 2. Using the PLZT according to claim 1, which has a reflective member on the back surface of the PLZT, and the light incident on the PLZT is reflected by the reflective member and modulated both in the forward and backward directions. A line scanner. 3. The scope of the above claim, characterized in that the counter electrodes are connected to a matrix of wiring, and a plurality of counter electrodes are sequentially applied from one end of the line to the other end by controlling switches in the row and column directions. A line scanner using the PLZT described in item 1. 4. P according to claim 1, which is used for a projector that projects images on a screen.
Line scanner using LZT.