JPS62226119A - Optical scanner - Google Patents

Abstract

PURPOSE:To obtain a large ratio between scanning light and incident light and a large scanning angle by forming a reflecting surface atop of both arms of a piezoelectric tuning fork. CONSTITUTION:The piezoelectric tuning fork 1 which is used as the oscillation source of an electronic wrist watch, etc., is used and vibrated while light beams are made incident on reflecting surfaces 4 and 5 provided on the end surfaces of the vibrating arms 2 and 3, thereby deflecting reflected light. When the scanning angle and deflecting angle are increased, plural piezoelectric tuning forks are cascaded so that optical axes are incident on the reflecting surfaces plural times. Consequently, efficiency, i.e. the ratio of the scanning light to the incident light is >=90% and the deflection angle is 10-30 deg.. Further, the scanning speed can be optionally set to 10,000-1,000,000rps.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is based on pressure '1! [Summary of the Invention] The present invention relates to an optical scanner for deflecting an optical axis by vibrating a piezoelectric sensor.The present invention involves making a light beam incident on a reflective surface provided at the tip of a tuning fork-shaped piezoelectric sensor, and detecting the reflected light. h; This method utilizes the fact that the pressure i-oscillator is deflected as the tuning fork is photographed.

[Prior art]

Conventional optical scanners have long used rotating mirrors. There is an optical scanner h that utilizes the scattering effect that occurs on the wavefront of longitudinal waves in a piezoelectric material.

[Problems to be solved by the invention] However, in the case of conventional rotating mirrors, the number of scans per second is slow at a maximum of 1,000 to 2,000 times, so high-speed scanning such as the horizontal scan of a television, which is approximately 15,750 times, is difficult. cannot be applied to.

In addition, in the case of a secondary optical scanner using longitudinal waves of a piezoelectric material, the amount of scattered light is not only poor, but also the scanning angle of the scattered light, that is, the deflection angle h, is as small as several degrees. , in the field of optical communications, the large scanning angle change required for display devices, ie 30 degrees to 60 degrees h;
I can't get it.

That's why this invention is so important! The purpose is to provide an optical scanner that can obtain a ratio of scanning light to incident light, that is, an efficiency of 1'l; a high scanning angle ht; Means for Solving the Problem] The optical scanner of the present invention is an electronic arm! Using a piezoelectric tuning fork that is used as an oscillation source such as a meter, a light beam is incident on the reflective surface provided on the end face of the vibrating arm, and the piezoelectric tuning fork is moved to capture the reflection. Light hz m 17
In order to increase the scanning angle, that is, the deflection angle,
Multiple optical axis /I: A plurality of piezoelectric tuning forks are connected in cascade so that the light is incident on the reflecting surface.

[Effect]

According to the above configuration of the present invention, the efficiency If, that is, the ratio of the scanning light to the incident light is 9° or more, and the deflection angle is 10° to 3ayh. Constant scan i If t'
j can be arbitrarily set from 10,000 times per second to 1,000,000 times per second. [Embodiment] Fig. 1 shows an original floating diagram of an optical scanner according to the present invention. As shown in Figure 1, this is a tuning fork type vibrator (hereinafter referred to as a piezoelectric tuning fork) made of IVi piezoelectric material. Piezoelectric tuning fork 102
A reflective surface 4.5 is formed at the tip of each vibrating arm (hereinafter referred to as both arms) 2.3.

Now, when the piezoelectric sound pressure vibrates like a tuning fork, both arms 2.3 move in the direction of arrow A and the direction of arrow B alternately.

At this time, the weight of the incident light is reflected at the reflecting surface 4.5, and the direction is P.
Scanning is performed in the same plane in the emission direction hz with the center being 0 and the direction of KRA and R11 being the limit. This emitted second light beam O is called a scanning light. If the maximum value of the relative angle due to the vibration of both arms is θ, then the difference in direction between the eight people and RB is 40. When crystal is used as the piezoelectric material, the maximum value of θ is as small as about 3 degrees.

In the configuration shown in FIG. 1, the maximum angular change that can be scanned is 12 degrees at most, which is insufficient for image display, etc. Therefore, it is possible to use two piezoelectric tuning forks and connect them in cascade (a scanning angle four times as large as this can be obtained, which is suitable for practical use).

The brush 2rgIJ is an embodiment of the optical scanner according to the present invention.It is constructed by connecting a piezoelectric tuning fork 6 and a piezoelectric tuning fork 7 in series.In this case, the maximum deflection angle when using the material listed in F is The temperature is 48 degrees, making it practically usable.

Figure 3 shows 62 piezoelectric tuning forks 8. which is another embodiment of the optical scanner according to the present invention. qhz is integrally constructed from plates of the same piezoelectric material, and is constructed as one member 1o. Most preferred is method h, which allows construction with high shape accuracy by performing exposure, development, and etching using photolithography.

FIG. 14 shows an example of the application of the optical scanner according to the present invention to a television projection apparatus.

Three optical scanners +-10 are installed, each with three primary color lights R.
, G, and B from the laser oscillator 11゜12.13, and after horizontal scanning, the prism 11
．． 15 and a cylindrical lens 16, each of the light beams is collimated into a single tree, which is vertically scanned with a rotation angle of -17 and projected onto a screen 181C. 19 motors.

〔Effect of the invention〕

As described above, by performing multiple reflections on the N incident surface at the tip of the piezoelectric tuning fork, the deflection angle necessary for the water collection device can be obtained. Also, the number of scans is 5000 times h1 etc.
,000 pixels is possible and can be applied to high-resolution display devices.
t is fully possible.

[Brief explanation of drawings]

Figure IE1 is an original diagram of the optical scanner of the present invention. 1...Piezoelectric tuning fork 2.3...Vibrating arm 4.5...N plane of incidence Figure 2 shows an embodiment of the optical scanner of the present invention. 6.7 ...Piezoelectric tuning fork '115 shows another embodiment of the optical scanner of the present invention. 8.9 ... Piezoelectric tuning fork 10 ... Optical scanner IX4 composed of one piece
The figure shows an application example of the optical scanner of the present invention. 10...An integrated optical scanner 11.
12.13... Laser oscillator 14.15...
... Prism 16 ... Cylindrical lens 17 ... Rotation → - 18 ... Screen 19 ... Motor and above Applicant Seiko Epson Corporation Figure 1 Figure 3

Claims (3)

[Claims] (1) An optical scanner characterized by having reflective surfaces formed at the tips of both arms of a piezoelectric tuning fork. (2) The optical scanner according to claim 1, wherein a plurality of the optical scanners are connected in series. (3) The optical scanner according to claim 1, wherein the optical scanner is integrally constructed from one piezoelectric material plate.