JPS60107515A - Distance detector - Google Patents

Abstract

PURPOSE:To improve the precision of distance detection by displacing an optical device through the operation of an electromagnetic driving means, deflecting the optical path of reflection from a subject and moving a light spot, and detecting the coincidence point of output levels of two split photodetecting elements. CONSTITUTION:Light from a light emitting element 11 strikes the subject 14 and is passed through a photodetection lens 7 and a prism 2 to form the light spot on a photodetecting element 1. The light spot of the reflected light strikes the majority of a photoelectric converting element 1-1 at the initial stage of the operation, so an integral output V1 is high and the optical path 8 is deflected according to the rightward movement of the prism 2 to decrease the output when the light spot becomes incident to a photoelectric converting element 1-2. The integral output V2 of the photoelectric converting element 1-2, on the other hand, varies from a low level to a high level. When the integral output levels V1 and V2 of the photoelectric converting elements 1-1 and 1-2 coincide with each other, the current voltage value VL is held by a capacitor.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a projection type distance detection device that utilizes the principles of triangulation.

Conventionally, this type of distance detecting device has a plurality of light receiving elements that receive all of the reflected light from the subject, a light emitting element that emits light that hits the subject, and which of the plurality of light receiving elements is used by which light receiving element. The entire distance is detected depending on whether the reflected light can be received. For example, JP-A-54
As is clear from the device disclosed in No. 40663, this type of device has a region where each of the plurality of light-receiving elements is conjugate with the distance to the subject, and a zone focus type that corresponds to all of them is required. This is for performing distance detection 7. A drawback of such an apparatus is that, since it is configured using a plurality of light-receiving element sounds, the distance to the subject cannot essentially be obtained continuously.

Also, JP-A-57-. As in No. 104809, a device has also been proposed which calculates the noise reduction of the photoelectric output of the divided light receiving element and detects the entire distance. However, in Maki's device, the calculation circuit is complicated, and at long distances, the reflected light itself decreases, so the error in the calculation circuit becomes large, and the detection results vary widely. are doing.

The present invention has focused on the above-mentioned problems, and provides a replacement chisel that can obtain continuous distance information, has a simple circuit configuration, and can perform accurate distance detection. The feature of the present invention is that the light is projected toward the subject and the reflected light is received on the i-
an optical device that receives light with the element and is placed in advance with a mechanical bias between the light receiving element and the light receiving lens;
A driving force in a direction opposite to the mechanical deflection is applied to the optical device by an electromagnetic driving means, and the optical displacement system scans the reflected light optical path. When the photoelectric output ratio of the light-receiving element reaches a predetermined value by displacement, the input electricity of the electromagnetic driving means is fully detected and used as distance information.This will be specifically explained below with reference to the drawings. The same parts in the figures are indicated by the same symbols. FIG. 1 is a diagram illustrating the principle of the present invention. 1 is a two-split light receiving element, 2 is a prism which is an optical device, 3 is a spring that provides mechanical bias, 4 is an electromagnetic driving means, for example, what is called an electromagnetic reciprocating part a replacement, and 5 is the above-mentioned 'camera'. Magnetic reciprocating drive ff
The power source t4, 6, is a variable resistor that controls the voltage value t supplied by the power source 5 to the electromagnetic reciprocating drive device 4.

7 is a two-part light receiving element 1. A light receiving lens 9 is disposed in front of the light receiving lens 7, and 9 is an optical axis of the light receiving lens 7. It is connected to the spring 5, one end to the prism 2, and the other end to the upper fixing member, respectively, and applies a force to the prism 2 in the left direction in the figure.

Further, the electromagnetic reciprocating drive device t4 has a movable shaft connected to the prism 2.

Next, the operation of the electromagnetic reciprocating drive device 4 will be explained. As shown in the graph of FIG. If we take F as the vertical axis, is it a linear characteristic? I have it. When the full voltage is supplied to the electromagnetic reciprocating drive device 4, the movable shaft moves rightward in FIG. Adjust the variable resistor 6 and apply the power to the electromagnetic reciprocating drive 4? When increased, the prism 2 balances the forces of the spring 3 and the movable shaft of the electromagnetic reciprocating drive device 4? While holding it, you will move to the right in the figure. The amount of movement of prism 2 is! There is a one-to-one correspondence with the electric power supplied to the magnetic reciprocating drive device 4.

Now, assuming that the optical path of the incident light entering the light-receiving lens 7 is 8, when the prism 2 is at the position (1), the light slot (fl) of the optical path 8 occurs at the position (1) of the two-split light-receiving element 1. 1!
5) Adjust the supply voltage v'2 of the reciprocating drive device 4 with the variable resistor 6, move the prism 2 to the right, and when the incident light is polarized by the prism 2, the surface of the 2-split light receiving element 1 will become a light spot. The position of prism 2 moving to the left in the figure (
In cases 2) and (3), the light spot position It on the surface of the two-part light receiving element 1 corresponds to (2) and (3), respectively. When the prism 2 is in position (3), a light spot is created exactly at the center of the two-split light-receiving element 2, and the two-split light-receiving element 2
The outputs of the respective photoelectric conversion elements match.

FIG. 3 shows an example of the structure of the electromagnetic reciprocating device 4.
31 is a movable shaft, 32 is a yoke, 35 is a permanent grinding stone attached to the shaft 31, 34.351ff electromagnetic coil, 3
This is a bearing for the 6.37u shaft 31.

When a voltage is supplied to the electromagnetic coils 34 and 35, the movable shaft 41 moves upward in accordance with the voltage value.

Is Fig. 4 (1k) and (b) the invention? It is a diagram used for distance detection by triangulation. , 11 are light emitting elements such as near-infrared light emitting diodes. Reference numeral 12 designates a light projection lens for producing an irradiation source beam, and 13 designates an optical axis of the light projection lens 12. 1-1 and 1-2 are respective photoelectric conversion elements of the two-split light receiving element 1. Light emitting element 11
The light irradiated from f is reflected by the objects 14 and 14', and the light passes through the optical paths 8 and 8'.IV! The light is then focused by the light receiving lens 7 to form an original spot on the surface of the light receiving element 1.

FIG. 5 is an example circuit diagram for obtaining an electric signal corresponding to distance. 51 is a modulation drive circuit for the light emitting element 11;
52, 5'7 are coupling capacitors for passing only the frequency components of light emitting element 11 irradiated n1 reflected by the temporary object n7t7 & dimming, 55.58 is an amplifier, and 54.59 is a signal component. 55.60 and 56.61 are the resistors and capacitors for forming the integrating circuit sound; 62 is the comparator;
When the photoelectric conversion element 1-1 side integrated output level V, ft, and the electric conversion element 1-2 side integrated output level v2 match, an inverted signal is output. 66 is a switch, and the switch is changed by the inverted signal of the comparator 62. 64 is a capacitor for storing or holding the voltage supplied to the electromagnetic reciprocating drive device 4. FIG. 6 shows the circuit output of FIG. 5. This is a waveform representing The horizontal axis is the number of movements of prism 2! It is.

Here, for the distance detection operation in Figure 4 (a) and (1)),
This will be explained in detail using the circuit shown in FIG. 5 and the waveforms shown in FIG.

With the configuration shown in FIG. 4, the light emitted from the light emitting element 11 hits the subject 14 located at a close distance, and the reflected light passes through the light receiving lens 7 and the prism 2 and forms a light spot on the light receiving element 1. FIG. 4(a) shows the above state. Now, adjust variable resistor 6 and get 11! When the entire voltage supplied to the magnetic reciprocating drive device @, a is reduced, the prism 2 becomes
At the initial stage of operation, when the light beam is overcome by the force of the spring 3 and moves to the right in the figure, the reflected light beam passes through the photoelectric conversion element 1-1.
As the prism 2 moves to the right, the optical path 8 becomes polarized.
When the light spot enters the photoelectric conversion element 1-2 side, the output decreases. On the contrary, the integrated output v,i of the photoelectric conversion element 1-2 changes from a low level to a high level. V and v2 in FIG. 6 are the n. 'tIL The voltage t supplied to the magnetic reciprocating drive device 4 is further increased, and the prism 2t is
When the comparator 62 is moved further, an intersection point between the integral output V and the integral output v2 occurs, and the photoelectric conversion element 1-1
．． 1-2, each integral output V1. When v2 matches, an inverted signal is output. When the integrated output V of the photoelectric conversion element 1-1 is higher than the integrated output V2 of the photoelectric conversion element 1-2, the output vc of the comparator 62 is at a high level, and when it is lower, the output vL is at a low level. It is interlocked with the switch 63 so that it is turned on when the output VC 62 is at a high level, and turned off when it is at a low level. When the switch 63 is on, the capacitor 64
samples the voltage value of the electromagnetic reciprocating drive device 4, and when turned off, holds the voltage value at that moment. V in Figure 6
L is the voltage waveform of the capacitor 64. , FIG. 6 shows the timing during the above operation. Power is supplied to the electromagnetic reciprocating drive device 4, the prism 2 moves by E, and the integral output level of each of the photoelectric conversion elements 1-1, 1-2 is V, ,
When vx matches, the output VC of the comparator 62 is inverted, and the voltage value supplied to the electromagnetic reciprocating drive device 4 is held by the capacitor 64 with that signal.

When the light is reflected by the object 14' located at a far distance as shown in FIG. 4(b), the light receiving element 1 may be A light spot is created at the location. As shown in FIGS. 4(a) and 4(b), the closer the object is, the more the light spot on the light receiving element 1 appears to the right, and the farther the object is, the more the light spot appears to the left. Therefore, when the subject is at a long distance as shown in Figure 4('b), compared to when the subject is at a short distance, even though the levels of the integral outputs V and V are the same, the amount of movement E of the prism 2 is In other words, the power supply voltage to the magnetic reciprocating drive device 4 is low. The above state is shown by the broken line graph in FIG. According to the present invention, the voltage value VL of the power supply voltage t memory or holding capacitor 64 to the electromagnetic reciprocating drive device kA
is a value corresponding to W separation. The closer the object is to the object, the higher the voltage value VL of the capacitor 62 is, and the farther the object is, the lower the voltage value VL is. In the figure, 71 is a reflecting mirror, and light receiving lens 13
Reflected light from the subject 14 that has passed through the meeting is guided to the light receiving element 1. 72 is a mounting member for the reflecting mirror 71 and has a shaft 72ai;
Rotates around the shaft 72a. Furthermore, it has @72bf,
It is connected to a pin 4a attached to the shaft 31 of the electromagnetic reciprocating device tA. The mounting member 72 is a spring 3,
In the figure, a clockwise rotational force is applied. Light receiving element 1
The original spot position on the surface changes depending on the position of the subject,
In Figure 7, the closer the object is, the more the light spot will appear at the top, and the farther the object is, the more the light spot will appear at the bottom.

Now, the electromagnetic reciprocating device 4 is fed, and when the mounting member 72 is rotated counterclockwise by the force of the spring 3, the light spot of the reflected light from the subject 14 is shifted to the surface t1 of the light receiving element 1.
The distance detection method and detection circuit, which move from top to bottom in the figure, have already been described, so they are omitted here. The rotation angles of the reflecting mirrors 71 have a one-to-one correspondence. When the object is close, the rotation angle of the reflecting mirror becomes larger, and the voltage supplied to the electromagnetic reciprocating device also becomes higher.

FIG. 8 shows another embodiment of the present invention, in which a parallel glass sound is used as the optical device. By supplying power to the electromagnetic reciprocating drive device 4 and rotating the parallel glass 81i, the light is polarized along the optical path 8 and the light spot generated on the light receiving element 1 is moved.

FIG. 9 shows another embodiment of the present invention, and the light receiving lens 7 itself? The light is changed by an electromagnetic reciprocating device 4, and the optical path 8 is polarized.

The distance detection method in the apparatuses shown in FIGS. 8 and 9 may be the same as the method already described. Further, the driving method for rotating the optical device as shown in FIG. 7 or FIG. 8 is not limited to the reciprocating drive device r1, but may be a rotary motion device such as a DC motor or a step motor.

As described above, in the present invention, the electromagnetic driving means is operated to displace the optical device i1.7, polarize the optical path r of the reflected light from the subject, move the two-split light receiving element (original socket) k, A matching point between the output levels of each of the divided light receiving elements is detected. By monitoring the input voltage to the electromagnetic drive means using the detection signal, an electric signal corresponding to the distance can be obtained. In the above embodiment, the electrical signal corresponding to the distance has been explained as a voltage value, but it is also possible to extract it as a current value. point? Since it is only necessary to detect the distance, there is no need for any complicated arithmetic circuits, and it is possible to accurately detect the distance. Another feature is that distance information can be continuously obtained as an f0 electrical signal. If this signal is used, it becomes easy to display the W-state, and the distance measuring device can also be connected, making it suitable for autofocus in cameras and the like.

Description of the invention'? Although we have described the case of a two-split photodetector, the photodetector can be used as it is as a position detection element (PS).
Even if replaced by D), this device is capable of manifestation.

[Brief explanation of the drawing]

Fig. 1 is a principle diagram of the present invention, Fig. 2 is a characteristic diagram of an electromagnetic reciprocating drive device, and Fig. 3 is a structural diagram of an example of an electromagnetic reciprocating drive device.
4(a) and 4(b) are one embodiment of the distance detection device of the present invention, FIG. 5 is a circuit diagram for distance detection of the present invention, FIG. 6 is an output waveform of the circuit diagram, and FIG. 9 to 9 show other embodiments of the distance detection device of the present invention. 1... Light receiving element 2... Grism 3... Spring 4... Electromagnetic reciprocating drive device 5... Power source 6 ...Variable resistor 7...Light receiving lens 11...Light emitting element 12...Emitting lens 14.14'...Subject 31...Movable axis 32...Yoke 33...Permanent magnet 54.35... Electromagnetic coil 36
．． 37...Bearing 1-1., 1-2...Photoelectric conversion element 51...Drive circuit 52.57...Coupling capacitor 53.58.
...Amplifier 54,59...Diode 55,60...Resistor 56,61,64...Capacitor 62...Comparator 63...Switch 71...Reflector 72...Mounting member 81... Parallel Galanu and above Applicant Seiko Koki Co., Ltd. Figure 1 V, A

Claims (1)

[Scope of Claims] (1) A light projecting means including a light emitting element and a light projecting lens is provided, and the distance to the object is determined by receiving the light projected from the light projecting means and reflected from the object. In a distance detection device for measuring a distance, a light receiving means includes a light receiving element and a light receiving lens for receiving reflected light from the subject, an optical device disposed between the light receiving element and the light receiving lens, and the optical device. an electromagnetic drive means that applies a driving force to the optical device in a direction opposite to a direction that imparts a mechanical bias to the device, and the amount of electricity input to the electromagnetic drive means becomes a distance signal.
Detection of cartilage and replacement vertebrae as percentage signs. (2. The distance detecting device according to claim 1, characterized in that the light receiving element is a two-divided A7v element. (3) Percentage gap in claim 2. The distance detecting device as described above is characterized in that when the photoelectric output ratio of the two-split light receiving element reaches a predetermined value, the input electric quantity of the electric power driving means is a signal corresponding to the distance. (4) Any one of claims 1.2 and 6.
In the distance detection device according to item 1, the optical device includes:
A distance detection device whose characteristic is that it is a prism. (5) Any one of claims 1.2 and 3.
In the distance detection device according to item 1, the optical device includes:
Distance detection device that is fully characterized by its reflection and hood. +6) Any one of claims 1.2 and 3
In the distance detection device according to item 1, the optical device includes:
Distance detection device characterized by being made of parallel glass (7) It has a light projecting means consisting of a light emitting element and a light projecting lens, and receives light and sound emitted from the light projecting means and reflected from a subject. What is the distance to the subject? In a distance detecting device for measuring, a light receiving means comprising a light receiving element and a light receiving lens for receiving reflected light from the object, a means for imparting a mechanical bias to the light receiving lens, a direction for imparting the mechanical bias; A distance detecting device comprising an electromagnetic driving means for applying a driving chip to the light receiving lens in the opposite direction, and an amount of electricity inputted to the electromagnetic driving means becomes a distance signal. (8) The distance detecting device according to claim 7, wherein the light receiving element is a two-divided f′Lfc element; (9) Permissible claim 8 The distance detecting device according to item 1, wherein the amount of electricity input to the electromagnetic driving means when the photoelectric output ratio of the two-split light receiving element reaches a predetermined value is a signal corresponding to the distance. .