JP3441495B2 - Target body - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for emitting and scanning a laser beam for setting a level and receiving the laser beam when performing marking, position setting and level setting. , A target object for displaying a light receiving state. 2. Description of the Related Art In recent years, a rotating laser level has been used to set a height standard in the fields of civil engineering and construction. [0003] The rotating laser level is obtained by rotating a laser beam from a laser emitting unit built in a main body around a vertical line,
A horizontal reference plane is formed by the laser light, and a horizontal reference line having a required height is formed by scanning the wall with the laser light. [0004] Laser light emitted from a laser emitting section at a rotating laser level includes visible light and invisible light. [0005] At a rotating laser level using visible light, an irradiation position of a laser beam is visually recognized by reflection from an object (object reflector) having a reflecting portion. Furthermore, in order to enhance visibility, a light receiving element with high sensitivity at the rotating laser level is provided, and reciprocating scanning is performed around the position where the reflected laser light from the target reflector provided at the irradiation position of the laser light is received. . At the rotating laser level using invisible light, the object is provided with a high-sensitivity photoelectric conversion element.
In some cases, the state of irradiation of a laser beam to an object is electrically displayed. [0007] However, the former object reflector has the advantage that the irradiation position of the laser beam can be visually recognized and the workability is good, but from the viewpoint of ensuring the safety of the worker, The output of the laser light is limited, making it difficult to view at a long distance. As described above, the apparent brightness is increased by detecting the reflected light from the target reflector and performing reciprocating scanning around the target reflector, but it is still difficult to view in a place exposed to direct sunlight. There was a problem that is. In the latter object, the speed at which light crosses the photoelectric conversion element becomes faster as the object becomes farther away, and a faster response speed is required for the photoelectric conversion element and the electric circuit of the object, resulting in a higher consumption rate. There was a problem in terms of electricity and lower prices. In view of such circumstances, the present invention makes it possible to easily find the position of a laser beam hitting a target object even in an outdoor measurement or an environment where the surroundings are bright with respect to the laser beam, thereby reducing the cost. , Realizing low power consumption. According to the present invention, there is provided a light-transmitting plate and a laser formed on the surface of the light-transmitting plate in an object irradiated with a laser beam emitted from a rotating laser level. light
A reflecting portion for reflecting light toward a rotating laser level;
A photoelectric conversion unit provided on the back of the transmission plate and divided vertically
And a display unit having a driving unit, wherein the light transmitting plate is
At the position of the laser light that is transmitted and received by the photoelectric conversion unit.
The driving unit is configured to irradiate the display unit with a laser beam
The present invention relates to an object configured to perform a corresponding display . The emitted laser light is divided into upper and lower beams.
The light enters the electric conversion unit and is photoelectrically converted. Irradiation of laser light
Depending on the position, an output difference from the upper and lower photoelectric units occurs, and the
The driving unit displays the light receiving state of the laser beam on the display unit based on the output difference . An embodiment of the present invention will be described below with reference to the drawings. Before describing this embodiment, the outline of the rotating laser level 11 will be first described with reference to FIG. In the figure, 1a is a laser modulation drive circuit,
The laser modulation drive circuit 1a modulates an operating current to the laser diode 1b of the laser light emitting unit 1, and the laser light emitting unit 1b emits a modulated linearly polarized laser light. The laser modulation drive circuit 1a is, as shown in FIG.
The modulation signal 30 is supplied to the switching element 3 via the amplifier 31.
2 to control the current supplied to the laser diode 1b. The laser light from the laser light emitting section 1 passes through a half mirror 2 or a perforated mirror and a λ / 4 wavelength plate 3 and is polarized into a circularly polarized laser light 4. The circularly polarized laser light 4 is rotated by a rotating pentaprism 5. And is rotationally scanned. The object reflector 6, which is one of the objects irradiated with the circularly polarized laser light 4, will be described with reference to FIG. The target reflector 6 includes a reflector 7 and a λ / 4 wavelength plate 8.
The circularly polarized laser light 4 passes through the λ / 4 wavelength plate 8 and is polarized into linearly polarized light.
The reflected light 4 ′ is reflected again by the λ / 4 wave plate 8.
Is transmitted to the circularly polarized laser light 4 so that the circularly polarized laser light 4 is circularly polarized in the reverse rotation direction. The reflected light 4 ′ enters the rotating laser level 11 and passes through the λ / 4 wavelength plate 3 via the pentaprism 5. The reflected light 4 ′ is linearly polarized by passing through the λ / 4 wavelength plate 3, and is reflected by the half mirror 2 toward the reflected light detector 9. The reflected light detector 9 is provided with a linearly polarizing plate 10, and the plane of polarization of the linearly polarizing plate 10 matches the plane of polarization of the reflected light 4 ′. Thus, the reflected light detector 9 detects the reflected light from the reflecting plate 7, and the rotating laser level 11 scans back and forth around the detected position. On the other hand, as shown in FIG. 8, when the circularly polarized laser light 4 from the rotating laser level 11 irradiates the unnecessary reflectors 12 other than the target reflector 6, the unnecessary reflectors 12 Of the reflected light is circularly polarized in the same rotational direction as the circularly polarized laser light 4. For this reason, when the reflected light from the unnecessary reflector 12 is polarized into linearly polarized light by the λ / 4 wavelength plate 3 inside the rotating laser level 11, the polarization direction differs from the linearly polarized light of the reflected light 4 ′ by 90 °. In other words, since the reflected light does not pass through the polarizing plate 10, the reflected light detector 9 does not detect it. Thus, the reflected light detector 9 receives only the reflected light from the target reflector 6. In the above, the case where the rotating laser level 11 itself checks the reflected light of the target reflector 6 has been described. Observe the reflection and diffusion at 6. Next, the target reflector 20 according to the present embodiment will be described with reference to FIGS. A reflecting portion 15 having a required width is formed on one side of a reflecting surface (front surface) of a vertically long rectangular light transmitting plate 13 made of plastic, glass, or the like. The reflecting portion 15 is obtained by superposing the λ / 4 wavelength plate 8 on the surface of the reflecting layer 14. Notches 16 are formed on the left and right side edges of the light transmitting plate 13 at positions vertically divided into two. A photoelectric conversion plate 17 is provided on the back surface of the light transmitting plate 13.
Is attached. A photovoltaic cell such as a solar cell is used for the photoelectric conversion plate 17, and the photoelectric conversion plate 17 is divided into an upper photoelectric conversion portion 17a and a lower photoelectric conversion portion 17b by a straight line connecting the left and right notches 16. Each of them independently outputs the light receiving state. A display 18 is provided at a required position on the surface of the light transmitting plate 13. The display 18 has a drive circuit 21 as shown in FIG. 5, and is driven by the drive circuit 21 with a downward arrow 19a, a coincidence line 19b, and an upward arrow 19c.
And a liquid crystal display unit 19 composed of The drive circuit 21 includes the upper photoelectric conversion unit 17
a, for driving and displaying any one of the downward arrow 19a, the matching line 19b, and the upward arrow 19c of the liquid crystal display unit 19 in accordance with the light receiving state of the lower photoelectric conversion unit 17b. Devices 23a and 23b and a control circuit 24 are provided. The operation will be described below. The laser beam reflected by the laser beam reflector 15 is the same as that shown in FIG. When the laser light is projected on the photoelectric conversion plate 17, different light receiving signals are emitted to the drive circuit 21 depending on the projected position. That is, the laser light is emitted from the photoelectric conversion plate 1.
7, the light receiving signal from the upper photoelectric conversion unit 17a is input to the tuning circuit 22a. On the other hand, since the lower photoelectric conversion unit 17b does not receive laser light, it does not input a light reception signal to the tuning circuit 22b. As shown in FIG. 5, the tuning circuit 22a cuts DC components and various noises due to sunlight and the like from the current signal a from the upper photoelectric conversion unit 17a, and converts only the signal by the laser beam into a voltage signal. Output as b. The tuning circuit 2
The signal from 2a is amplified by the signal processor 23a, detected, and obtained as DC converted to DC. By using a tuning circuit as the load of the photoelectric conversion element, the influence of disturbance light such as sunlight is reduced as compared with a resistive load, so that a signal having a good S / N and a large amplitude can be obtained. Can be Therefore, it can be configured with an amplifier circuit having a small gain band product, and low power consumption and low cost can be realized. Similarly, the signal from the lower photoelectric converter 17b is converted into a DC signal from which noise has been removed by the tuning circuit 22b and the signal processor 23b. Signals from the signal processors 23a and 23b are input to the control circuit 24 to compare the two signals. The upper photoelectric conversion unit 17a
Receives the laser light, the signal processor 23a
Is large, the control circuit 24 drives the upward arrow 19c to display to the operator that the laser light receiving position is to be moved upward. Note that a delay circuit or the like may be provided in the drive circuit 21 and the display of the liquid crystal display unit 19 may be held for a predetermined time by a signal input from the tuning circuit 22a. Thus, since the worker can check the reflection of the laser light and also check the liquid crystal display unit 19, he can perform the operation without any trouble even when the external light is strong and the check of the laser light is difficult. Next, the laser light is applied to the lower photoelectric conversion section 17b.
When the light beam is projected on the screen, the downward arrow 19a is displayed in the same manner, and the operator is instructed to move the light receiving position of the laser beam downward. Further, when the laser beam is projected just on the boundary between the upper photoelectric conversion unit 17a and the lower photoelectric conversion unit 17b, the signal values from the signal processors 23a and 23b become the same, and the deviation between the two signals is obtained. Becomes 0. At this time, the control circuit 24 drives and displays the matching line 19b to notify the operator that the position of the target reflector 20 for receiving the laser beam is appropriate. An operator makes a mark on a wall surface or the like using the notch 16. FIG. 4 shows another embodiment, in which a buzzer 25 is provided in place of the liquid crystal display section 19, and when the target reflector 20 is aligned, the buzzer 25 sounds. Is according to the light receiving state of the photoelectric conversion plate 17,
Change how the buzzer 25 sounds. Further, the liquid crystal display unit 19 and the buzzer 25 may be used together as the display means, or a display other than the liquid crystal may be used. Also, the reflection part 15, the photoelectric conversion plate 1
The position and shape of 7 can be changed as appropriate. In general, the spot diameter of the laser beam is small. Therefore, when the laser beam is projected near the boundary between the upper photoelectric conversion unit 17a and the lower photoelectric conversion unit 17b, the downward arrow 19a due to camera shake and other vibrations will The line 19b and the upward arrow 19c may be frequently switched, which may make alignment difficult. In such a case, the light transmission plate 13 is made of a light diffusion and transmission material, or the light transmission plate 1
The spot diameter of the laser beam on the light-receiving surface of the photoelectric conversion plate 17 may be enlarged by making the back surface of 3 a diffusion surface or the like. Alternatively, when external light such as sunlight is incident from the light transmitting plate 13, the photoelectric conversion plate 17 receives the light and causes a malfunction. A polarizing plate that transmits only light may be provided. Although the above embodiment has been described with reference to an object having a reflecting portion, it is needless to say that the present invention can be applied to an object having no reflecting portion. As described above, according to the present invention, a laser beam projected on a target object can be reliably confirmed even in an environment where external light is strong or at a long distance, and the laser beam , The scanning position can be easily confirmed, and further, the excellent effects of being inexpensive and having a long battery life are exhibited.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing one embodiment of the present invention. FIG. 2 is a front side view of the same. FIG. 3 is a front perspective view of the same. FIG. 4 is a front view of another embodiment. FIG. 5 is a block diagram showing a driving circuit of a liquid crystal display unit in the embodiment. FIG. 6 is a basic configuration diagram of a rotating laser level. FIG. 7 is an explanatory diagram of a target reflector provided for a rotating laser level. FIG. 8 is an explanatory diagram showing a relationship between a rotating laser level and target reflectors and unnecessary reflectors. FIG. 9 is a circuit diagram showing an example of laser modulation driving. [Description of Signs] 13 Light transmitting plate 15 Reflecting portion 17 Photoelectric conversion plate 17a Upper photoelectric conversion portion 17b Lower photoelectric conversion portion 19 Liquid crystal display portion 19a Down arrow 19b Matching line 19c Up arrow 21 Drive circuit

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshikazu Adagawa 75-1 Hasunuma-cho, Itabashi-ku, Tokyo Inside Topcon Corporation (56) References JP-A-62-95419 (JP, A) (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01C 5/00 G01C 15/00

Claims (1)

(57) [Claims 1] A light transmitting plate and a light transmitting plate for an object irradiated with laser light emitted from a rotating laser level.
Directs the laser beam formed on the plate surface to the rotating laser level
A reflecting portion for reflecting light, and an upper portion provided on a back surface of the light transmitting plate.
A display unit including a photoelectric conversion unit divided below and a driving unit
And transmitted through the light transmitting plate and received by the photoelectric conversion unit.
The driving unit performs the display based on the position of the laser light to be emitted.
To make the display correspond to the laser beam irradiation position
An object characterized by being achieved .