JPS61110116A - Light beam generator - Google Patents

Abstract

PURPOSE:To detect accurately the receiving direction of light reflected from a light reflecting means by placing light converging means in a light receiving optical path and a light receiving means at the focal position. CONSTITUTION:A light beam S0 generated from a laser beam generator 2 as a light source is divided into two light beams S, Swith a rotating mirror 4. A light receiver 6 receiving light reflected from a light reflecting means is placed, and light converging means 9 are placed in the light receiving optical path of the light receiver 6 so that the receiver 6 is positioned at the focal position.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention generates a light beam having a predetermined spread toward a light reflecting means that reflects light in an incident direction, and Regarding a light beam generating device equipped with a means for receiving light, in particular as a guiding means for automatically moving a moving object such as an autonomous working vehicle or an automatic guided vehicle in a factory along a preset trajectory. The present invention relates to a suitable light beam generating device.

[Conventional technology]

As shown in FIG. 8, this type of light beam generating device generates a light beam toward a light reflecting means (cc), such as a corner cube prism, which is installed in advance at a predetermined position and reflects the light in the direction of incidence. In order to generate a light beam having a predetermined spread from the device (^) and to detect information regarding the position and direction with respect to the light reflecting means based on the light receiving direction at the time when the reflected light from the light reflecting means (cc) is received. (For example, Japanese Patent Application Laid-open No. 15881/1983 or Japanese Patent Application No. 95401/1987, which the present applicant has already filed).

However, with the conventional configuration described above, especially if the light beam generated from the light beam generator (A) has a diffusive property with respect to the direction (angle) to be detected, there will be an error ( Δθ) occurs, and the error varies greatly depending on the distance between the light beam generator (A) and the light reflecting means (cc).

Therefore, in order to reduce the diffusion of the light beam generated from the light beam generator in unnecessary directions, it is necessary to use a laser beam generator with low light diffusivity or use multiple lenses to prevent diffusion. , resulting in a complex and expensive system.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide a light beam generating device equipped with a means for accurately detecting the receiving direction of the reflected light from the light reflecting means. Moreover, in order to achieve the purpose, it is realized with a simple configuration.

[Means for solving problems]

In order to achieve the above object, the light beam generating device according to the present invention is characterized in that a condensing means is provided so that the light receiving means is located at a focal position within the light receiving optical path of the light receiving means, Its actions and effects are as follows.

[For production]

That is, as shown in FIG. 7, by providing a condensing means (9) such as a convex lens in the light receiving optical path and arranging the light receiving means (6) at its focal position, the light reflecting means (cc)
Only when the reflected light is on the optical axis connecting the condensing means (9) and the light receiving means (6), that is, only the reflected light from a certain direction is received.

〔Effect of the invention〕

With the above features, the following excellent effects have been achieved.

In other words, even if the light beam generated from the light beam generator has a diffusive property, the light receiving means only receives reflected light from a certain direction, so the light reflecting means is not affected by the diffusion of the light beam used. The direction can now be detected with high accuracy.

Further, the light collecting means has selectivity in the light collecting direction,
For example, it is possible to improve the detection accuracy in a specific light receiving direction by configuring the sensor to have light focusing ability only in the horizontal direction and not in the vertical direction.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Figures 1 and 2, on the mounting frame (1),
A light beam (So) is generated by a laser emitter (2) as a light source, and the direction of generation is changed by a deflection mirror (3) to a direction perpendicular (Z) to the mounting frame (1).
The entire light beam (So) is pivoted around the emission optical axis (Z), that is, the axis in the vertical direction, by a motor (t2) so as to be rotatable and scannable, and around the horizontal axis (X), the motor ( Rotating mirror (4) rotationally driven by ?1K)
, a predetermined direction (Y
) on both sides of the deflection mirror (3
) and the rotating mirror (4) and the light beam (So
), a beam splitter (5) is provided on the optical axis (Z) of the beam splitter (5) and the rotating mirror (4).
The two light beams (S), which are incident through (
Light reflecting means (cc) not shown in the emission direction (Y) of S)
A light receiver (6) is provided to receive reflected light from the
It constitutes a light beam generator (A) which has a predetermined spread angle (φ) in the vertical direction and can freely scan the emission direction in the horizontal direction.

Then, by continuously rotating the rotating mirror (4) by a motor (Mx), the scanning device (B
), the slit (8) provided in the light emitting surface (7), (7)
), (8), the light beam (So) is scanned at high speed in the vertical direction on both sides of the predetermined direction (Y) at a predetermined spread angle (φ), and during the scanning, the light reflecting means (c
c) the reflected light from the rotating mirror (4) and the beam splitter (5) is received by one light receiver (6), and each axis (X) at the time of receiving the light;
Encoder (EX) installed at (Z).

Based on the rotation angle detection result by (Ex), the light receiving direction, that is, the light reflecting means (cc) with respect to the light beam generator (A)
) is detected and used as a means for guiding the moving direction of a moving object.

Note that the two light beams (S) of the scanning device (B)
, (S) are provided with a convex lens (9a) as a condensing means (9) for the light receiver (6).
).

(9a) is vertically divided into two parts, and the light receiver (6) is located at the focal point of the two parts.

Moreover, the slits (8) and (8) are the convex lenses (9a).

(9a), wherein the two light beams (S), (S) are formed by a convex lens (9a),
(9a) prevents the light from being diffused in an unnecessary direction (horizontal direction).

Next, a control circuit for a motor (M2) that rotates and scans the scanning device (B) around the vertical axis (Z) will be explained.

As shown in Figure 3, the control signals (CA), (cm) for forward rotation, reverse rotation, and stop of the motor (M2) and the motor (
The rotation end detection signal (
One NAND based on SL), (SR) and
gate (G1) and two AND gates (h), (h
), the two limit switches (SWt, ), (SW
The control signal (CA'), (cm') of the motor driver (11) is calculated so that the scanning device (B) rotates within the range regulated by t).

In other words, the limit switches (S & 4L), (SW,
l) is ON, the control signal (CA),
Even if (Ca) is in a state instructing forward rotation or reverse rotation, the instruction is invalidated to prevent scanning device (B) from being driven any further, and rotation and stopping in the opposite direction to the current rotation direction are performed. It is only valid.

Another example will be described below.

As shown in FIG. 4, instead of using a convex lens with a slit (9a) as a condensing means (9) for the light receiver (6), a cylindrical lens (9b) is used whose condensing direction is horizontal, that is, the light beam ( It may also be arranged in a direction (horizontal direction) different from the direction in which the light spreads (So), so that the light condensing effect is exerted only on reflected light.

Moreover, as shown in FIGS. 5 and 6, the convex lens (
9a) is divided into two so that only the light receiver (6) exhibits a light condensing effect, and the convex lens (9a) is not divided and the reflected light from the light reflecting means (cc) is branched. The beam splitter (5) connects the light beams (S), (S
) is arranged to form a slit (8) in the portion through which the light beam (S
), a plurality of slit non-convex lenses (9C) and light receivers (6) are provided to condense the reflected light from the light reflecting means (cc) on both sides of the emission direction (Y) of (S), respectively.
It may be configured such that only the light receiver (6) exhibits a light condensing effect.

When a plurality of light receivers (6) are provided in this way, the light beams (S) can be detected on both sides of the emission direction (Y) of the light beams (S) without detecting the rotation angle of the rotating mirror (4). From which side of the receiver (6) the reflected light was received
) and (6). Moreover, since the convex lens (9C) itself does not have a slit, even if a plurality of convex lenses (9c) and light receivers (6) are used, the configuration is simple and does not become expensive.

Further, the light receiver (6) is configured such that its light receiving range becomes wider in the longitudinal direction of the slit (8), that is, in the spreading direction of the light beam (S), and the light receiving position changes due to vibration in the vertical direction. It may also be possible to prevent the occurrence of light reception errors due to.

Furthermore, by providing a plurality of the deflecting mirrors (3), the degree of freedom in arranging the laser emitter (2) is increased, so there is an effect that the entire device can be made compact.

[Brief explanation of the drawing]

The drawings show an embodiment of a light beam generating device according to the present invention,
Fig. 1 is a partially cutaway perspective view showing the overall configuration, Fig. 2 is a side sectional view of the main parts, Fig. 3 is a block diagram of the motor rotation control circuit, and Fig. 4 shows another embodiment of the light condensing means. FIG. 5 is an explanatory diagram showing the main configuration of another embodiment, FIG. 6 is a side view showing the overall configuration, FIG. 7 is a detailed explanatory diagram of the present invention, and FIG. is an explanatory diagram of a conventional example. (cc)...Light reflecting means, (6)...
Light receiving means, (9)... Light collecting means, (9a),
(9c)... Convex lens, (9b)...
・Cylindrical lens.

Claims (1)

[Claims] [1] Generating a light beam having a predetermined spread toward a light reflecting means (cc) that reflects light in the incident direction, and receiving reflected light from the light reflecting means (cc). A light beam generating device comprising a means (6) for detecting the light receiving means (6), the light receiving means (6) having the light receiving means (6) at its focal position within the light receiving optical path of the light receiving means (6).
6) A light beam generating device characterized in that a condensing means (9) is provided so that the light beam generating device (9) is located so that the condensing means (9) is located so that the condensing means (9) is located so that [2] The light according to claim 1, wherein the light condensing means (9) is configured so as not to exhibit a condensing effect in the direction in which the light beam spreads. Beam generator. [3] A patent characterized in that the condensing means (9) is a convex lens (9a), and is configured to have a hole in the passage range of the light beam so as not to exhibit a condensing effect. A light beam generator according to claim 2. [4] The condensing means (9) is a cylindrical lens (9b), and is arranged so that its cylindrical axis direction and the spreading direction of the light beam coincide with each other, so that it does not exhibit a condensing effect. The light beam generating device according to claim 2, characterized in that: