JP2000112661A - Method for adjusting optical axis of scanning light for optical scanning touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily adjust an optical axis of scanning light for performing optical scanning of a specified position (e.g. a center part) of a retroreflective body even when the scanning light is the light in the invisible region. SOLUTION: An optical scanning touch panel for performing the optical scanning of a retroreflector 13 by the scanning light 18 outputted from a light emitting part by rotation of a scan mirror is constituted by forming slits Sas, Sbs and Sae, Sbe with approximately the same width as beam diameter of the scanning light 18 at a starting position and an ending position of the optical scanning of the retroreflector 13 and providing photodetectors 30as to 30be to face the slits Sas to Sbe on the opposite side of an optical scanning surface of the retroreflector 13 and optical axis adjusting mechanism (mechanism for adjusting a mounting angle of optical scanning units 11a, 11b and a substrate 10 by a screw) for adjusting the optical axis of the scanning light 18 and the optical axis adjusting mechanism is adjusted so that a detected value of the photodetectors 30as to 30be provided at the starting position and the ending position of the optical scanning becomes maximum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to optical scanning of a retroreflector with light output from a light emitting section by rotation of a scan mirror, and light reflected by the retroreflector is received via reflection of the scan mirror. The present invention relates to a method of adjusting a scanning light optical axis of a light scanning type touch panel that receives light at a unit.

[0002]

2. Description of the Related Art A conventional optical scanning type touch panel is configured as shown in FIG. That is, reference numeral 10 denotes a rectangular substrate such as an optical filter provided on the front surface of the display screen of the display device, and optical scanning units 11a and 11b are arranged at both corners on one side of the substrate 10, and one surface of the substrate 10 An elongated frame 12 is fixed to three sides of the optical scanning units 11a and 11b except for a mounting portion, and a retroreflector 13 is attached to an inner surface of the frame 12. The retroreflector 13 is formed in a tape shape, for example, and is adhered to the inner surface of the frame 12.

In the optical scanning unit 11a, as shown in FIG. 12, a fixed portion (not shown) of a unit support plate 25 is fixed to a substrate 10 with an adhesive or the like, and a substantially L portion integrated with the fixed portion is provided.
The unit main body 14 is mounted on the letter-shaped support portion 27 and is attached so that the angle can be adjusted. Unit body 14
The lower surface is formed with a substantially L-shaped L-shaped groove 15 which is loosely fitted to the support portion 27, and a light-emitting element (eg, a laser diode) 16 such as a semiconductor laser device and a light-receiving element 1
7, a refraction prism 19 for refracting laser light 18 (hereinafter simply referred to as light 18) as scanning light output from the light emitting element 16 and a half for transmitting the refracted light 18 are provided on the upper surface. A prism 21 having a mirror 20 and a scan mirror 22 are provided. The scan mirror 22 is rotatably provided by a pulse motor 23. The optical scanning unit 11b has the same configuration as the optical scanning unit 11a.

The light 18 output from the light emitting element 16 is
Is refracted by the refraction prism 19, passes through the half mirror 20 and the prism 21, is reflected by the scan mirror 22, and irradiates the retroreflector 13. In this retroreflector 13,
The reflected light is reflected by the scan mirror 22 on the substantially same optical path as the incident light, is reflected and refracted by the half mirror 20 of the prism 21, and is received by the light receiving element 17. The light 18 is scanned by an angle θ (for example, about 90 °) by the rotation of the scan mirror 22 by the pulse motor 23. If there is an object (for example, a finger or a pen) 24 in this optical scanning range, the light 18 is blocked by the object 24, and the angle θ of the object 24 is detected based on the light receiving energy of the light receiving element 17. You. Assuming that the angles of the object 24 detected in the respective scans of the optical scanning units 11a and 11b are θ1 and θ2, the object 2
The coordinates (Px, Py) of the position P on the coordinate plane (on the substrate 10) designated by 4 are obtained by the principle of triangulation.

[0005] That is, as schematically shown in FIG.
Assuming that the length from the optical scanning unit 11a to the optical scanning unit 11b on the substrate 10 is L, the following relationship holds: Py = Px · tan θ1 (1) Py = (L−Px) · tan θ2 (2) Based on the equations (1) and (2), Px = {tan θ2 / (tan θ1 + tan θ2)} · L (3) Py = {tan θ1 / tan θ2 / (tan θ1 + tan θ2)} · L (4)

[0006]

However, FIG.
In the conventional example shown in (1), there is a problem that the adjustment of the scanning light optical axis for irradiating the light 18 to a predetermined position (for example, the center) of the retroreflector 13 becomes complicated. In particular, when the light 18 is invisible light (for example, infrared light) (usually, invisible light is often used), there is a problem that the adjustment of the scanning light optical axis becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. Even when light (for example, laser light) output from a light emitting unit (for example, laser diode) is invisible light (for example, infrared light), light is recursively reflected. Position (for example, the center) of the reflective body
It is an object of the present invention to make it possible to easily adjust the optical axis of a scanning light for irradiating light.

[0008]

According to a first aspect of the present invention, there is provided a method for adjusting the optical axis of a scanning light, wherein the retroreflector is optically scanned with light output from a light emitting unit by rotation of a scanning mirror. In the optical scanning touch panel that receives the light reflected by the light-receiving unit through the reflection of the scan mirror, slits with the same width as the beam diameter of the scanning light are formed at the start and end positions of the optical scanning of the retroreflector And, provided a photodetector facing the slit on the opposite side of the optical scanning surface of the retroreflector,
An optical axis adjusting mechanism for adjusting the optical axis of the scanning light is provided, and the optical axis adjusting mechanism is adjusted so that the detection value of the photodetector is maximized. Since the optical axis adjustment mechanism is adjusted so that the detection values of the photodetectors provided at the start position and the end position of the optical scanning become maximum, even when the scanning light is invisible light, the scanning light is reflected by the retroreflector. The optical axis adjustment for adjusting the scanning so as to scan a predetermined position (for example, the center) can be easily performed.

According to a second aspect of the present invention, in the first aspect, a slit is formed in the retroreflector so that the optical axis of the scanning light can be adjusted without forming a slit in the retroreflector. Instead, a slit is formed at a position corresponding to the start position and the end position of the optical scanning of the frame to which the retroreflector is attached, and a photodetector facing the slit is provided on the opposite side of the retroreflector mounting surface of the frame, Before attaching the retroreflector to the slit portion of the frame, the optical axis adjustment mechanism is adjusted so that the detection value of the photodetector is maximized.

According to a third aspect of the present invention, in the first aspect, a slit is formed in the retroreflector so that the optical axis of the scanning light can be adjusted without forming the slit in the retroreflector. Instead, a slit is formed at a position corresponding to the optical scanning start and end positions of the frame on which the retroreflector is mounted, and a photodetector facing the slit is provided on the opposite side of the retroreflector mounting surface of the frame. Before the retroreflector is attached to the frame, the optical axis adjustment mechanism is adjusted so that the detection value of the photodetector is maximized.

According to a fourth aspect of the present invention, there is provided a method of adjusting a scanning light optical axis, wherein a light output from a light emitting section by rotation of a scan mirror is used to optically scan a retroreflector, and light reflected by the retroreflector is scanned. In an optical scanning type touch panel that receives light at a light receiving unit through reflection of a mirror, a slit having substantially the same width as the beam diameter of the scanning light is provided on the optical scanning surface near the start position and the end position of optical scanning of the retroreflector. Is provided, an optical axis adjusting mechanism for adjusting the optical axis of the scanning light is provided, and the optical axis adjusting mechanism is adjusted so that the light receiving energy of the light receiving unit is maximized.

Since the optical axis adjustment mechanism is adjusted so that the light receiving energy of the light receiving portions provided at the start position and the end position of the optical scanning becomes maximum, even if the scanning light is invisible light, the scanning light is recursive. The optical axis of the scanning light, which is adjusted to scan a predetermined position (for example, the center) of the reflector, can be easily performed. Further, the optical axis adjusting mechanism is adjusted so that the light receiving energy of the light receiving section is maximized.
It is not necessary to provide a slit in the retroreflective body or the frame unlike the invention of the above-mentioned invention, and it is not necessary to provide a photodetector.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, even when the scanning light is invisible infrared light, the light emitting portion is provided so that the approximate position of the scanning light can be visually confirmed. A laser diode that outputs laser light in the infrared region, and a light-emitting film that emits visible light upon incidence of the laser light is attached to the light scanning surface of the adjustment jig.

The invention according to claim 6 is the invention according to claims 1, 2, 3, and 4.
Or, in the invention described in 5 above, in order to simplify the configuration of the optical axis adjustment mechanism, the optical axis adjustment mechanism is fixed to the unit body on which the light emitting unit, the light receiving unit and the scan mirror are fixed, and to the substrate forming the coordinate plane. It comprises a unit support plate and a plurality of screws for attaching the unit body to the unit support plate so as to adjust the angle.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a scanning light optical axis adjusting method for an optical scanning type touch panel according to the present invention will be described below with reference to FIGS. FIG. 1 is a plan view of an optical scanning type touch panel in which a front vessel is not shown. In FIG. 1, the same parts as those in FIGS. In FIG. 1, reference numeral 10 denotes a substrate, 11a, 11
b is an optical scanning unit, 12 is a frame 12, and 13 is a retroreflector, which are configured in the same manner as in FIG.

As shown in FIGS. 2 and 3, a light 18 as a scanning light is located at a start position and an end position of the frame 12 and the retroreflector 13 for optical scanning by the optical scanning units 11a and 11b. Slits Sas, Sbs and Sae, Sbe having substantially the same width as the beam diameter are formed. On the opposite side of the light scanning surface of the retroreflector 13, photodiodes 30as, 30bs and 30a as photodetectors facing the slits Sas, Sbs and Sae and Sbe.
e and 30be are provided. The photodiodes 30as, 30bs and 30ae, 30be are provided with ribs 33 projecting inward from the outer edge 32 of the front vessel 31.
And the corresponding slits Sas, Sbs and Sa
e, Light 18 passing through Sbe is detected. The substrate 10 and the front vessel 31 are fixedly attached to each other with a support column 34, a holder 35, and screws 36. 37 denotes a transparent filter film, and 38 denotes a display screen portion of the plasma display.

The optical scanning unit 11a is shown in FIGS.
As shown in FIG. 12, a fixing portion 26 of the unit support plate 25 is fixed to the substrate 10 with an adhesive or the like.
The unit body 1 is placed on a substantially L-shaped support portion 27 integrated with
4 is mounted and mounted so that the angle can be freely adjusted. That is, the unit main body 14 is provided with the support portion 27 on the lower surface.
A light-emitting element 16 and a light-receiving element 17 are housed therein.
A refraction prism 19 for refracting the light 18 output from the light emitting element 16, a prism 21 having a half mirror 20 for transmitting the refracted light 18, and a scan mirror 22 are provided. The scan mirror 22 is a pulse motor. 23 so as to be freely rotatable. The optical scanning unit 11b has the same configuration as the optical scanning unit 11a.

As shown in FIG. 5, spring receiving holes 40, 40, and 40 are formed in the support portion 27 of the unit support plate 25 at three positions, that is, both ends of the L-shape and a bent portion. ,
At the center of the spring receiving holes 40, 40, 40, screw holes 4 are provided.
1, 41, 41 are formed. Further, the spring receiving hole 40,
Screw insertion holes 42, 42, 42 corresponding to 40, 40
Are drilled, and screws 4 are inserted through springs 43, 43, 43.
4, 44, 44 are attached. The unit body 14, the unit support plate 25, and the screws 44, 44, 44
Constitutes an optical axis adjusting mechanism, and three screws 44, 44, 44
By adjusting the degree of screwing into the screw holes 41, 41, 41, the optical axis of the light 18 that scans the optical scanning surface of the retroreflector 13 can be changed.

As shown in FIG. 6, a laser driver 50 is connected to the light emitting element 16, and the pulse motor 2
A motor driver 51 is connected to 3. The light receiving element 17 includes a current / voltage conversion circuit 52 for converting a current corresponding to the received light energy into a voltage, an A / D (analog / digital) conversion circuit 53, and a primary reflected light separation circuit 5.
4 are sequentially coupled, and the primary reflected light separation circuit 54 separates a signal corresponding to the primary reflected light (maximum received light energy) of the scan mirror 22 from the output signal of the A / D conversion circuit 53. And outputs an optical scanning start pulse. 55 is an oscillator for outputting a measuring clock, 56 is a counter,
The counter 56 controls the oscillator 55 in one cycle of the optical scanning start pulse obtained by the primary reflected light separation circuit 54.
Is counted. A comparator 60 compares the output voltage of the current / voltage conversion circuit 52 with a reference voltage, and outputs an object detection signal corresponding to the light blocked by the object 24. The photodiodes 30as and 30ae have current / voltage conversion circuits 62 and 6 for converting a current corresponding to the received light energy into a voltage.
A / D conversion circuits 64 and 65 are connected to the output side of the current / voltage conversion circuits 62 and 63, respectively.

Reference numeral 70 denotes an MPU (microprocessor unit). The MPU 70 includes a ROM (read only memory), a RAM (random access memory), a counter, and a register. Object 24 based on the object detection signal of
Is calculated. Further, the MPU 70
The scanning angle θ2 of the object 24 is calculated based on the count value signal of the counter based on the light receiving energy of the light receiving element of the optical scanning unit 11b described later and the object detection signal of the comparator. Further, the MPU 70 determines the angles θ1, θ2
Is applied to the above equations (3) and (4) to calculate the coordinates (Px, Py) of the position P on the coordinate plane (on the substrate 10) indicated by the object 24, and to obtain a corresponding signal (for example, (A coordinate display signal) to the display device 72. Also,
The MPU 70 controls the photodiodes 30as, 30as based on output signals of the A / D conversion circuits 64, 65.
ae corresponding to the received light energy of the display device 7
2 and a level value corresponding to the received light energy is displayed.

A laser driver and a motor driver are connected to the light emitting element and the pulse motor of the optical scanning unit 11b, similarly to the optical scanning unit 11a. As in the optical scanning unit 11a, a current-voltage conversion circuit, an A / D conversion circuit, a primary reflected light separation circuit, an oscillator, a counter and a comparator are coupled to the light receiving element of the optical scanning unit 11b. The count value signal of the counter and the object detection signal of the comparator are output to the MPU 70.

The photodiodes 30bs and 30be
In the same manner as the photodiodes 30as and 30ae, a current / voltage conversion circuit for converting a current corresponding to the received light energy to a voltage and an A / D conversion circuit are sequentially coupled,
Based on the output signal of this A / D conversion circuit (not shown in FIG. 6), the MPU 70
A signal corresponding to the received energy of s, 30be is output to the display device 72, and a level value corresponding to the received energy is displayed.

Next, the operation of the scanning optical axis adjusting method according to the present invention in the optical scanning type touch panel shown in FIGS. 1 to 6 will be described. A: First, the adjustment of the scanning optical axis of the optical scanning by the optical scanning unit 11a will be described. (A) The current corresponding to the received light energy of the photodiodes 30as and 30ae provided at the start position and the end position of the optical scanning is converted into a voltage by the current / voltage conversion circuits 62 and 63, and the A / D conversion circuit 64 The digital signal is converted into a digital signal at 65 and input to the MPU 70. Based on the output signal from the MPU 70, the display device 72
A level value corresponding to the received energy of 0as, 30ae is displayed. (B) While watching the display on the display device 72, insert the three screws 44, 44, 44 of the optical axis adjusting mechanism into the screw holes 41, 41, 41 so that the detection values of the photodiodes 30as, 30ae become maximum. Adjust the degree of screwing. The detection values of the photodiodes 30as and 30ae are maximized when the light 18 that scans the optical scanning surface of the retroreflector 13 is used.
Is coincident with the central axis in the longitudinal direction of the slits Sas and Sae. For this reason, even when the light 18 is an invisible light, a scanning light optical axis adjustment for adjusting the light 18 to scan a predetermined position (for example, a center portion) of the retroreflector 13 is performed.
Easy to do.

B: Next, the adjustment of the scanning optical axis of the optical scanning by the optical scanning unit 11b will be described. (A) A current corresponding to the received light energy of the photodiodes 30bs and 30be provided at the start position and the end position of the optical scanning is converted into a voltage by a current / voltage conversion circuit, and A / A
The digital signal is converted into a digital signal by the D conversion circuit and is input to the MPU 70. Based on the output signal from the MPU 70, the display device 72 displays the level value corresponding to the received light energy of the photodiodes 30bs and 30be in the above-mentioned A.
(A). (B) While watching the display on the display device 72, insert the three screws 44, 44, 44 of the optical axis adjusting mechanism into the screw holes 41, 41, 41 so that the detection values of the photodiodes 30bs, 30be become maximum. (That is, the optical axis of the light 18 that scans the optical scanning surface of the retroreflector 13 so that the optical axis of the light 18 coincides with the central axis in the longitudinal direction of the slits Sbs and Sbe). Same as (b). For this reason, the scanning light optical axis adjustment for adjusting the light 18 to scan the predetermined position of the retroreflector 13 can be easily performed.

C: Next, the operation of detecting the coordinate position on the substrate 10 designated by the object 24 will be described. (A) Scan mirror 22 rotated by pulse motor 23
Rotates the retroreflector 13 with the light 18 output from the light emitting element 16, and the light 18 reflected by the retroreflector 13 passes through the scan mirror 22 to the light receiving element 17.
Is received at. This operation (a) is performed by the optical scanning unit 11.
Although the operation is performed at a, the same operation is performed in the optical scanning unit 11b.

(B) The current corresponding to the light receiving energy of the light receiving element 17 is converted into a voltage by a current / voltage conversion circuit 52, and is converted into a digital signal by an A / D conversion circuit 53.
The light is input to the primary reflected light separation circuit 54, and an optical scanning start pulse corresponding to the primary reflected light of the scan mirror 22 is output from the primary reflected light separation circuit 54. This optical scanning start pulse 1
The measurement clock in the cycle is counted by the counter 56, and a count signal is output to the MPU 70.

(C) The output voltage of the current / voltage conversion circuit 52 is compared with a reference voltage by the comparator 60, and the comparator 60 outputs an object detection signal corresponding to light blocked by the object 24 to the MP.
Output to U70. The MPU 70 determines the target 2 based on the count signal of the counter 56 and the target detection signal of the comparator 60.
4 is calculated. The operations (b) and (c) are operations in the optical scanning unit 11a, but also operate in the optical scanning unit 11b, and the MPU 70 calculates the scanning angle θ2 of the object 24. And MPU
70 calculates the coordinates (Px, Py) of the position P on the coordinate plane designated by the object 24 by performing an operation by applying the obtained angles θ1 and θ2 to the equations (3) and (4). The signal is output to the display device 72.

In the above embodiment, the case where slits are formed in the retroreflector and the frame has been described.
The present invention is not limited to this, and the present invention can be used even when a slit is formed only in the frame. For example, as shown in FIGS.
Light 1 at a position corresponding to the start position and end position of
8, slits Sas, Sbs and Sae, Sbe having substantially the same width as the beam diameter of 8 are formed, and a retroreflector 13 is attached to the slits of the frame 12 except for the slits. Before attaching, the three screws 44, 4 of the optical axis adjustment mechanism are set so that the detection values of the photodiodes 30as, 30bs, 30ae, 30be become maximum.
The degree of screwing of the screws 4 and 44 into the screw holes 41 may be adjusted. In this case, after adjusting the optical axis, the retroreflector 13 is attached to the non-adhered portion of the retroreflector 13 including the slit portion of the frame 12.

Alternatively, in the embodiment shown in FIGS. 7 and 8, instead of adjusting the optical axis in a state in which the retroreflector 13 is attached to a portion other than the slit portion of the frame 12, the recursive Before mounting the reflector 13, the photodiodes 30as, 30bs, 30ae, 30b
The degree of screwing of the three screws 44, 44, 44 of the optical axis adjusting mechanism into the screw holes 41, 41, 41 may be adjusted so that the detected value of e becomes maximum. In this case, the retroreflector 13 is attached to the entire frame 12 after the optical axis adjustment.

In the above embodiment, the case where the slit is formed in the frame and the retroreflector or the frame has been described. However, the present invention is not limited to this, and the slit is formed in the frame and the retroreflector or the frame. Can be used in the case where an adjustment jig is used instead of forming the above. For example, as shown in FIG. 9 and FIG. 10, the slits are not formed at the start position and the end position of the optical scanning of the frame 12 and the retroreflector 13, and
8, rectangular plate-shaped adjustment jigs 80as, 80bs and 80 each having slits Sas, Sbs, Sae, and Sbe (only Sas is shown in the figure) having substantially the same width as the beam diameter of FIG.
ae, 80be (only 80as is shown in the figure) may be used.

That is, the adjustment jig 80 is provided on the optical scanning surface side near the optical scanning start position and the end position of the retroreflector 13.
as, 80bs and 80ae, 80be detachably attached, and the light receiving element 1 at the start position and the end position of optical scanning
7, the screw holes 41, 41, 4 of the three screws 44, 44, 44 of the optical axis adjusting mechanism are set so that the received light energy of the optical axis 7 becomes maximum.
Adjust the degree of screwing into 1. In this case, the photodiodes 30as and 30ae, the current / voltage conversion circuits 62 and 63, and the A / D conversion circuits 64 and 65 in FIG. 6 are omitted, and the A / D conversion circuit 5 as shown by a dotted line in FIG.
3 is added to the MPU 70, and a signal corresponding to the light receiving energy of the light receiving element 17 is output to the MPU 70 based on the output of the A / D conversion circuit 53. A function is added to display the detected values (level values) at the start position and the main rail position.

The adjusting jigs 80as, 80bs, 80
A light-emitting film (not shown) that emits visible light upon incidence of light 18 (laser light) is attached to the surfaces of ae and 80be. The light-emitting film is formed, for example, by applying a phosphor or phosphor powder that emits fluorescence or phosphorescence by infrared light to a transparent film using a binder. Therefore, at the beginning of the optical axis adjustment, the light 18 is applied to the adjustment jig 80as,
Which side of the surface of the 80bs, 80ae, and 80be is incident can be visually confirmed, and the time required for optical axis adjustment can be shortened. The present invention can also be used in a case where the light emitting film is not attached.

In the above embodiment, when adjusting the optical axis, the MP
The display device coupled to the output side of U was used to make it possible to visually check the maximum light detection of the photodiode or the maximum light reception energy of the light receiving element. However, the present invention is not limited to this. Voltage conversion circuits 62 and 63 or 5
The present invention can also be used in a case where the output signal of No. 2 is led to an oscilloscope, and the oscilloscope is configured so that the maximum light detection of the photodiodes 30as and 30ae or the maximum light reception energy of the light receiving element 17 can be observed.

In the above embodiment, the optical axis adjusting mechanism comprises a unit body to which a light emitting unit, a light receiving unit and a scan mirror are fixed, a unit support plate fixed to a substrate forming a coordinate plane, and a unit support plate to which the unit body is fixed. A plurality of screws attached to the screw holes so that the angles can be adjusted, and the case where the optical axis of the scanning light is adjusted by adjusting the degree of screwing of the plurality of screws into the screw holes has been described. However, the present invention is not limited to this. Instead, any device that adjusts the optical axis of the scanning light may be used.

[0035]

According to the first aspect of the present invention, there is provided a method for adjusting the optical axis of a scanning light, wherein a slit having substantially the same width as the beam diameter of the scanning light is formed at a starting position and an ending position of optical scanning of the retroreflector. Providing a photodetector facing the slit on the opposite side of the optical scanning surface of the reflective reflector, providing an optical axis adjustment mechanism for adjusting the optical axis of the scanning light,
Since the optical axis adjustment mechanism is adjusted so that the detection values of the photodetectors provided at the start position and the end position of the optical scanning become maximum, even if the scanning light is invisible light, the scanning light is recursive. The optical axis of the scanning light, which is adjusted to scan at a predetermined position (for example, the center) of the chromatic reflector, can be easily performed.

According to a second aspect of the present invention, in the first aspect of the present invention, instead of forming a slit in the retroreflector, the frame on which the retroreflector is attached is located at a position corresponding to the start position and the end position of optical scanning. Form a slit, provide a photodetector facing the slit on the opposite side of the retroreflector mounting surface of the frame, and before mounting the retroreflector on the slit portion of the frame, the detection value of the photodetector is maximized Since the optical axis adjusting mechanism is adjusted as described above, the optical axis of the scanning light can be adjusted without forming a slit in the retroreflector.

According to a third aspect of the present invention, in the first aspect of the present invention, instead of forming a slit in the retroreflector, the frame on which the retroreflector is mounted is located at a position corresponding to the start position and the end position of optical scanning. A slit is formed, and a photodetector facing the slit is provided on the opposite side of the retroreflector mounting surface of the frame.Before mounting the retroreflector on the frame, the light is detected so that the detection value of the photodetector is maximized. Since the axis adjusting mechanism is configured to be adjusted, the optical axis of the scanning light can be adjusted without forming a slit in the retroreflector.

According to a fourth aspect of the present invention, there is provided a method of adjusting a scanning light optical axis, wherein a light output from a light emitting section by rotation of a scan mirror is used to optically scan a retroreflector, and light reflected by the retroreflector is scanned. In an optical scanning type touch panel that receives light at a light receiving unit through reflection of a mirror, a slit having substantially the same width as the beam diameter of the scanning light is provided on the optical scanning surface near the start position and the end position of optical scanning of the retroreflector. Since an adjustment jig provided with is provided, an optical axis adjustment mechanism for adjusting the optical axis of the scanning light is provided, and the optical axis adjustment mechanism is adjusted so that the light receiving energy of the light receiving unit is maximized. Even when the scanning light is invisible light, the scanning light optical axis adjustment for adjusting the scanning light to scan a predetermined position (for example, the center) of the retroreflector can be easily performed. Furthermore, since the optical axis adjusting mechanism is adjusted so that the light receiving energy of the light receiving unit is maximized, it is not necessary to provide a slit in the retroreflector or the frame as in the invention of claims 1 to 3, and the photodetector It is not necessary to provide.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the light emitting portion is a laser diode for outputting a laser beam in the infrared region, and the laser beam is incident on the optical scanning surface side of the adjusting jig by the incidence of the laser beam. Since the light emitting film that emits light is attached, the approximate position of the scanning light that scans the retroreflector when the scanning light is laser light in the infrared region can be visually confirmed, and the adjustment time is shortened. can do.

The invention according to claim 6 is the invention according to claims 1, 2, 3, and 4.
Or In the invention according to 5, wherein the optical axis adjustment mechanism comprises: a light emitting unit;
A unit body to which the light receiving unit and the scan mirror are fixed;
Since the unit support plate fixed to the substrate forming the coordinate plane and the plurality of screws for attaching the unit body to the unit support plate so that the angle can be adjusted are provided, the configuration of the optical axis adjustment mechanism can be simplified.

[Brief description of the drawings]

FIG. 1 is a plan view of an optical scanning type touch panel for implementing an embodiment of a scanning optical axis adjusting method according to the present invention.

FIG. 2 is an enlarged cross-sectional view taken along line AA of a portion of the retroreflector 13 in FIG.

FIG. 3 is an enlarged cross-sectional view taken along the line BB of the retroreflector 13 in FIG. 2;

FIG. 4 is a diagram showing C- of the optical scanning unit 11a in FIG. 1;
It is a C-line enlarged sectional view.

FIG. 5 is a diagram showing optical scanning units 11a and 11b shown in FIGS. 1 and 4;
5 is an exploded perspective view of the optical axis adjusting mechanism used in the method of the present invention.

FIG. 6 is a block diagram of a circuit portion of an optical scanning type touch panel for implementing an embodiment of a scanning optical axis adjusting method according to the present invention.

7 shows another embodiment of the present invention and is an enlarged sectional view corresponding to FIG.

8 is an enlarged cross-sectional view taken along line DD of a portion of the retroreflector 13 in FIG. 7;

FIG. 9 shows still another embodiment of the present invention.
It is an expanded sectional view of the adjustment jig 80as part when the adjustment jig 80as is used instead of forming a slit in the frame 12 and the retroreflective body 13 or the frame 12.

FIG. 10 is a diagram showing E- of the adjustment jig 80as portion in FIG. 9;
It is an E line expanded sectional view.

FIG. 11 is a plan view of an optical scanning type touch panel in a conventional example.

FIG. 12 shows the optical scanning units 11a and 11 in FIG.
It is a side view which shows the attachment state of b.

FIG. 13 is an explanatory diagram showing the principle of triangulation for coordinate detection.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... board | substrate (an example of a coordinate plane) 11a, 11b ... Optical scanning unit, 13 ... Retroreflective body, 16 ... Light emitting element (for example, laser diode), 17 ... Light receiving element, 1
8. Light output from the light emitting element 16 (eg, laser light)
Reference numeral 22: scan mirror, 23: pulse motor (an example of a motor), 24: target object, 25: unit support plate, 26: fixing portion, 27: support portion, 30as, 3
0ae, 30bs, 30be: photodiode (an example of a photodetector), 31: front vessel, 32: outer edge of front vessel 31, 33 ... rib, 34 ...
Supports, 35: Holder, 36: Screw, 37: Filter membrane, 38: Display screen, 40: Spring receiving hole, 41
... Screw hole, 42 ... Screw insertion hole, 43 ... Spring,
44 screws (main parts of an example of an optical axis adjustment mechanism);
Laser driver, 51 ... Motor driver, 52, 6
2, 63 ... current / voltage conversion circuit, 53, 64, 65 ...
A / D conversion circuit, 54... Primary reflected light separation circuit, 55
... oscillator, 56 ... counter, 60 ... comparator, 70 ...
MPU (microprocessor), 72 display device, 8
0as, 80ae, 80bs, 80be ... jig for adjustment,
Sas, Sae, Sbs, Sbe ... Slit, θ, θ
1, θ2: scanning angle.

Claims (6)

[Claims] 1. An optical scanning method in which a retroreflector is optically scanned with light output from a light emitting unit by rotation of a scan mirror, and light reflected by the retroreflector is received by a light receiving unit via reflection of the scan mirror. In the touch panel, a slit having substantially the same width as the beam diameter of the scanning light is formed at the start position and the end position of the optical scanning of the retroreflector, and the slit is formed on the opposite side of the optical scanning surface of the retroreflector. Providing an optical detector facing, providing an optical axis adjustment mechanism for adjusting the optical axis of the scanning light,
A method for adjusting a scanning light optical axis of an optical scanning type touch panel, wherein the optical axis adjusting mechanism is adjusted so that a detection value of the photodetector is maximized. 2. A light scanning device in which a retroreflector is optically scanned with light output from a light emitting unit by rotation of a scan mirror, and light reflected by the retroreflector is received by a light receiving unit via reflection of the scan mirror. In the type touch panel, a slit having substantially the same width as the beam diameter of the scanning light is formed at a position corresponding to the start position and the end position of the optical scanning of the frame on which the retroreflector is mounted, and the retroreflector mounting surface of the frame is formed. Provide a photodetector facing the slit on the opposite side, provide an optical axis adjustment mechanism for adjusting the optical axis of the scanning light, before attaching the retroreflector to the slit portion of the frame,
A method for adjusting a scanning light optical axis of an optical scanning type touch panel, wherein the optical axis adjusting mechanism is adjusted so that a detection value of the photodetector is maximized. 3. An optical scanning method in which a retroreflector is optically scanned by light output from a light emitting unit by rotation of a scan mirror, and light reflected by the retroreflector is received by a light receiving unit via reflection of the scan mirror. In the type touch panel, a slit having substantially the same width as the beam diameter of the scanning light is formed at a position corresponding to the start position and the end position of the optical scanning of the frame on which the retroreflector is mounted, and the retroreflector mounting surface of the frame is formed. Provide a photodetector facing the slit on the opposite side of the slit, provide an optical axis adjustment mechanism for adjusting the optical axis of the scanning light, before attaching the retroreflector to the frame, the detection value of the photodetector Adjusting the optical axis adjusting mechanism so that the maximum value is obtained. 4. A light scanning device which optically scans a retroreflector with light output from a light emitting unit by rotation of a scan mirror, and receives light reflected by the retroreflector at a light receiving unit via reflection of the scan mirror. In the type touch panel, on the optical scanning surface side near the start position and the end position of the optical scanning of the retroreflector, an adjustment jig provided with a slit having substantially the same width as the beam diameter of the scanning light is provided, An optical axis adjusting mechanism for adjusting the optical axis of the scanning light, wherein the optical axis adjusting mechanism is adjusted so that the light receiving energy of the light receiving unit is maximized. Method. 5. A light emitting portion is a laser diode for outputting laser light in an infrared region, and a light emitting film for emitting visible light by incidence of the laser light is attached to the light scanning surface of the adjusting jig. The method for adjusting a scanning light optical axis of an optical scanning type touch panel according to claim 4. 6. An optical axis adjusting mechanism, comprising: a unit body to which a light emitting unit, a light receiving unit, and a scan mirror are fixed; a unit support plate fixed to a substrate forming a coordinate plane; and an angle between the unit body and the unit support plate. 6. The method for adjusting a scanning light optical axis of an optical scanning type touch panel according to claim 1, comprising a plurality of screws that are attached so as to be adjustable.