JPH07280939A - Reflection measuring apparatus - Google Patents

Abstract

PURPOSE:To provide a reflection measuring apparatus which accurate measurement of distance to an object to be measured can be carried out and which secures the exposure reference to a human body even when a measurable distance is long and at a very close distance, in addition to its small physical constitution. CONSTITUTION:An aluminum-adhered mirror is formed on one side of a base material of a reflection mirror 33 and a dielectric multi-layer film mirror with a reflection factor thereof lower than that of the aluminum-adhered mirror is formed on the other side. When the distance to an object to be measured exceeds a fixed value, a light beam is reflected with the aluminum-adhered mirror and when the distance to the object to be measured is less than a fixed value, it is reflected with the dielectric multi-layer film mirror. The center of the light beam emitted from a semiconductor laser diode 21 always reflects on a virtual extension of a rotating shaft of a turntable 32 positioned on the surface of the aluminum-adhered mirror to be transmitted through a collimation lens 40. Since the collimation lens 40 is a multi-focus lens with a focal length thereof larger on the outer circumference part than that at the center part, the uniformization of the density of the quantity of light of the light beam passing through the collimation lens 40 is made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection measuring device for measuring a distance between a measuring object and an object to be measured,
For example, it relates to a reflection measuring device for a vehicle.

[0002]

2. Description of the Related Art For example, a conventional emitting optical system used in a vehicle reflection measuring apparatus expands its irradiation range by expanding a light beam emitted from a semiconductor laser. However, in this method, when there are many vehicles within the irradiation range, vehicles other than the vehicle in front of the measurement target are also detected, so that the distance to the vehicle in front cannot be accurately detected. It is also not possible to accurately distinguish the object and the vehicle body.

In order to solve such a problem, as a vehicle reflection measuring apparatus for irradiating a light beam passing through an exit lens in parallel to an object to be measured, Japanese Patent Laid-Open No. 5-66263, FIG. 16 and FIG. The thing shown in the Kaihei 4-279890 publication is known. JP-A-5-6626
In the publication No. 3, as shown in FIG. 16, a light beam emitted from a laser oscillator 61 is made parallel by an emission lens 62, and the parallel light beam is reflected by a scanning mirror 63 to irradiate an object to be measured with the object to be measured. The light beam reflected from the object is reflected by the scanning mirror 63 and guided to the detector to measure the distance to the object to be measured. At this time, the scanning mirror 63 is rotated to oscillate the light beam to perform scanning.

Further, as shown in FIG. 17, the laser beam emitted from the laser diode 64 is reflected by a polygon mirror 65.
A reflection measuring device for a vehicle that reflects the light on the surface and then passes through the emission lens 66 is conceivable. However, in this structure, although the center of rotation 65a of the polygon mirror 65 is on the optical axis of the emitting lens 66, the center of the reflecting surface 65b is displaced from the optical axis as shown in FIG. The generated laser beam does not pass through the same point on the reflecting surface 65b. Therefore, the astigmatism of the exit lens 66 becomes large due to the deviation of the incident angle to the exit lens 66. Therefore, the light amount of the light beam in the downward direction of FIGS. 17 and 18 is actually leftward in the irradiation direction of the light beam. An asymmetric light quantity density pattern having a high density and a low light quantity density of light rays in the right direction is formed. In this case, since the same measurement target is irradiated with light beams having different powers, there are cases where the same measurement target is detected as objects having a sense of depth and different distances.

In order to solve this problem, Japanese Patent Laid-Open No. 4-27
According to Japanese Patent No. 9890, the light beams emitted from the laser diode are first made into a parallel bundle by a collimator lens, the parallel light beams are reflected by a polygon mirror, and the polygon mirror is rotated to oscillate the light beams for scanning. A lens for correcting the non-uniformity of the light quantity density generated at this time is provided at the light beam exit.

Further, the measurable distance of the vehicle reflection measuring apparatus becomes longer as the power of the emitted light beam becomes larger as shown in the following equation (1), and therefore the output is high in order to secure the maximum detection distance of 100 m or more. It is necessary to use laser diodes. Measurable distance ∝k × (power of emitted light) ^1/4・ ・ ・ (1) The laser light emitted from the laser diode having such a high output has a pole of several meters or less when the vehicle is stopped or running at low speed. When viewed from a short distance, it exceeds the exposure radiation limit (Class 1 AEL) of JIS C 6802, which is a radiation safety standard for eyes. In such a measuring device, the emission power of the laser diode is set to zero when the vehicle is stopped or when the vehicle is traveling at low speed so that the radiation exposure limit is not exceeded.

[0007]

[Patent Document 1] Japanese Unexamined Patent Publication No.
In the conventional vehicular reflection measuring apparatus disclosed in Japanese Patent Publication No. 66263, it is necessary to correct the light amount density distribution of the emitted light beam because the light beam is reflected by the scanning mirror after passing through the emission lens to irradiate the object. However, there is a problem in that the size of the measuring device becomes large because a scanning mirror larger than the diameter of the light beam transmitted through the emission lens is required.

Further, the one disclosed in Japanese Patent Laid-Open No. 4-279890 requires a lens for correcting the light quantity density distribution of the light beam, which causes a problem that the device becomes large. Further, such a lens has a problem that the manufacturing cost is high.
Theoretically, in order to obtain outgoing light with a uniform distribution even if the light rays are scanned, as shown in FIG. 19, the rotation center of the reflecting mirror 72 is on the optical axis of the outgoing lens 73 and the outgoing lens is It is conceivable that the laser diode 71 emits a light beam toward this principal point, which coincides with the principal point of 73, but this is not feasible.

Furthermore, since a vehicle distance information cannot be obtained at a low speed with a measuring device which makes the emission power of the laser diode zero when the vehicle is stopped or running at a low speed, future tracking control such as starting vehicle starting warning, etc. Cannot add function. As a countermeasure, there is a method of lowering the current value to reduce the output of the laser diode, but at most, it can be reduced only about 1/10,
It is difficult to satisfy the radiation exposure limit while satisfying the maximum detection distance of 100 m or more. As another method, there is a method of increasing the distance between the emitting lens and the laser diode to reduce the power of the light beam emitted from the lens, but there is a problem that the size of the measuring device becomes large. As another method, the pulse width of the laser light (light emission time)
There is a problem that the circuit becomes complicated and the cost becomes high, though there is a measure to reduce the width.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a reflection measuring apparatus which accurately measures the distance to an object to be measured and has a small physique. Another object of the present invention is to provide a reflection measuring device having a long measurable distance and protecting the exposure standard for the human body even at a close range.

[0011]

According to a first aspect of the present invention, there is provided a reflection measuring device, comprising: a reflecting member having a first reflecting surface for reflecting a light beam; and a first reflecting member of the reflecting member. Driving means for rotating the first reflecting surface, a light source provided so that the center of the outgoing light ray is reflected on the axis of rotation of the reflecting member, and a light ray reflected by the first reflecting surface. An emission lens that makes the light rays substantially parallel, a light beam that has passed through the emission lens is reflected by the object to be measured, and a light receiving unit that receives the reflected light beam, a light receiving time at the light receiving unit, and a light beam emitted from the light source. Calculating means for calculating the distance to the object to be measured from the difference between the output time and the output time.

Further, it is desirable that the distortion curvature of the emission lens of the reflection measuring apparatus of the present invention becomes larger from the central portion toward the outer peripheral portion as described in claim 2. Furthermore, the said reflection member of the reflection measuring apparatus of this invention is Claim 3.
As described above, it is desirable to provide the second reflecting surface having a lower reflectance than the first reflecting surface on the other surface.

[0013]

According to the reflection measuring apparatus of the first aspect of the present invention, since the center of the light beam emitted from the light source is located at the rotation center of the reflecting member, the light amount of the light beam scanned by rotating the reflecting member. The density is low at the center and high at both ends. Therefore, it is possible to measure the distance to the object to be measured in front of the front without any practical problems.

According to the reflection measuring device of the second aspect of the present invention, the light beam emitted from the light source is scanned by rotating the reflecting mirror by increasing the distortion curvature of the emitting lens from the central portion toward the outer peripheral portion. However, since the light quantity density becomes uniform within the scanning range, it is possible to measure the correct distance from the measured object. According to the reflection measuring device of claim 3 of the present invention, the second reflecting surface having a lower reflectance than the first reflecting surface is provided on the reflecting member, so that the light is emitted from the light source at the second reflecting surface. Since the light quantity density of the light ray can be reduced by reflecting the light ray, even if a person is present at a position very close to the measuring device, the exposure by the light ray can be suppressed within the safety standard.

[0015]

Embodiments of the present invention will be described with reference to the drawings. (First Embodiment) FIGS. 1 to 8 show a vehicle reflection measuring apparatus according to a first embodiment of the present invention. Housing 1 of measuring device 1
In 0, a light beam irradiation unit 20, a light beam reflection unit 30, a collimator lens 40, a light receiving lens 51, a light receiving element 52, and a circuit board 53 are housed.

The light beam irradiation unit 20 is composed of a semiconductor laser diode 21, a circuit board 22 having a drive circuit for the semiconductor laser diode 21, and a diaphragm plate 23 for narrowing the light beam emitted from the semiconductor laser diode 21. The semiconductor laser diode 21 has a large output of 10 W to 20 W and is driven by the drive circuit of the circuit board 22 to emit infrared pulsed light having a wavelength λ: 860 nm. Semiconductor laser diode 21
A through hole is provided in the portion of the diaphragm plate 23 corresponding to the emission position of the light beam, and the light beam is emitted to the light ray reflecting portion 30 through the through hole. The other rays are blocked by the diaphragm plate 23.

The light beam reflector 30 includes a step motor 31,
It comprises a turntable 32 and a reflecting mirror 33. Step motor 31
Is supplied with a drive current from a power supply unit (not shown) and rotates the reflecting mirror 33 fixed to the turntable 32 by a predetermined dispersion angle, and when the scanning of all angles is completed, the reflecting mirror 33 is inverted in the opposite direction. To scan. As shown in FIG. 3, the reflecting mirror 33 includes a reflecting mirror main body 35 and a fixing member 36 for fixing the reflecting mirror main body 35 to the rotary table 32. The base material 35a of the reflecting mirror body 35 is made of glass, plastic, or metal. An aluminum contact mirror 35b is formed on one surface of the substrate 35a, and a dielectric multilayer mirror 35c having a lower reflectance than the aluminum contact mirror 35b is formed on the other surface. The reflecting mirror 33 can make the aluminum contact mirror 35b or the dielectric multilayer film mirror 35c face the semiconductor laser diode 21, as shown in FIGS. 3 and 4, by rotating the step motor 31. The virtual extension line of the rotary shaft of the turntable 32 is located on the surface of the aluminum contact mirror 35b, and the turntable 3 is located on the surface of the aluminum contact mirror 35b.
The reflecting mirror 33 is fixed to the turntable 32 such that the optical axis of the collimator lens 40 passes along a virtual extension line of the second rotation axis. As shown in FIG. 4, the virtual extension line of the rotation axis of the rotary table 32 is not located on the surface of the dielectric multilayer mirror 35c, but the dielectric multilayer mirror 35c reflects light rays at a short distance. Since it is only for the measurement object, the non-uniformity of the light amount density within the close range is within a range where there is no practical problem. The aluminum contact mirror 35b has a reflectance of about 90 to 95% in the wavelength range of the semiconductor laser diode 21.
Is formed.

The collimator lens 40 is a plastic lens having a diameter of 40 mm and a focal length f ₁ : 40 mm (F naber 1) at the center. The light beam reflected by the reflecting mirror 33 is irradiated by the collimator lens 40 toward the object to be measured with an angle slightly wider than parallel. This is because, even if the light rays are converged to the closed side even slightly, the light rays having a high light quantity density are irradiated to the outside, which is very dangerous. The material of the collimator lens 40 is made of acrylic or polycarbonate containing pigment for cutting the transmittance of visible light to almost zero. In the present invention, no pigment may be mixed. What is required of the material of the collimator lens 40 is that the index ratio n is as high as n ≧ 1.45 and the surface accuracy is as high as λ / 4. Further, as shown in FIG. 5, the collimator lens 40 is a multifocal lens having a short focal length f ₁ at the central portion and a long focal length f _{2 at the} outer peripheral portion. This is because when a lens having the same focal length over the entire area of the lens is used, as shown in FIG. 9, the light quantity density of the light beam becomes low at the center and becomes higher at both ends, but the distribution becomes non-uniform, which is symmetrical. . The cause is that the virtual emission position of the semiconductor laser diode 21 is shifted to the left and right, which is affected by the aberration of the collimator lens 50 having the same focal length, and the distance of the light ray passing through the outer peripheral portion is longer than the distance of the light ray passing through the central portion. Because it will be. Considering from the viewpoint of measurement distance, there is a concern that the same object to be measured may be detected as objects having a sense of depth and different distances. However, if it is used for the purpose of scanning a narrow area in front of the front and measuring the distance to the object to be measured, it is practically possible to use the reflection measuring apparatus having the configuration of FIG. 9 as a modified example 1 of the first embodiment. There is no hindrance.

The collimator lens 40 is preferably a multifocal lens in which the focal length continuously or progressively increases from the central portion to the outer peripheral portion. This is for equalizing the distances from the virtual emitting position of the semiconductor laser diode 21 to the lens center and both ends of the lens. In the present invention, the correction effect can be obtained even with a lens having three or more focal lengths.

The light receiving lens 51 has a wide angle range (± 10 °).
The Fresnel lens has a special shape with high light collection efficiency and a focal length f ₃ = 43 mm. Light receiving lens 51
The material is acrylic or polycarbonate containing a visible light cut pigment similar to the collimator lens 40. In the present invention, it is possible to use an aspherical lens as the light receiving lens. The light receiving element 52 is a PIN photodiode. In the present invention, an avalanche photodiode can be used instead of the PIN photodiode.
An arithmetic circuit (not shown) mounted on the circuit board 53 reflects the object to be measured and receives the light receiving element 5 via the light receiving lens 51.
The distance from the object to be measured is calculated from the difference between the light receiving time and the light exiting time of the light ray incident on 2.

Measurement distance = (time of receiving light−time of emitting) × speed of light × 1/2 (2) Here, the higher the output of the semiconductor laser diode 21, the more the formula (1) shows. As described above, the measurable object to be measured has a long detection distance, but the issue is how to comply with the radiation safety standard for eyes within the irradiation range of the measuring apparatus 1 (hereinafter, "radiation safety standard for eyes" is referred to as AEL). Become. Next, an example is shown of the design value of each member that satisfies the AEL and the distance between each member.

The measuring device 1 has a JIS
It is assumed that the class 1 laser defined in 1) is used. Figure
As shown in FIG. 6, a pupil is provided near the outer surface 10a of the housing 10.
When attached, the diameter φ of the entrance aperture of the pupil is set to 7 mm
Make sure the incoming ray does not exceed the AEL for a single pulse
Distance L₁, L₂, L₃, L_sAnd the collimator lens 40
Design and shape. Where L₁: Semiconductor laser diode
Distance between the cord 21 and the reflecting mirror 33, L₂: Reflector 33 and
Distance from the remeter lens 40, L₃= L₁+ L ₂,
L_s: Collimator lens 40 and outer surface 1 of housing 10
It is the distance from 0a. As an example, wavelength 860nm, output
23W, full width at half maximum is 20 ° in the vertical direction and 7 ° in the horizontal direction
When using the conductor laser diode 21, L₁= L₂=
20 mm, L ₃= L₁+ L₂= 40 mm. Colime
Incident half angle θ of the data lens 40₁= 5 °, emission half angle θ₂=
When 0.4 °, the radiant energy Q incident on the pupil is Q =
3 x 10^-7(J). On the other hand, single pulse AELsi
ngle = 4.18 × 10^-7(J), so Q <AEL
It has become single and has not exceeded AEL.

Exposure AEL from a single pulse in a pulse train
train is expressed by the following equations (3) and (4). AELtrain = AELsingle × N^-1/4 ... (3) N = f_q× t (4) where N: total number of pulses in the application time reference, f_q: Semi-conductor
Oscillation frequency of body laser diode 21, t: According to JIS
It is the prescribed application time. In equation (3) and equation (4),
AELsingle = 4.18 × 10^-7(J), f_q= 1KH
_z, T = 1000 _secSubstituting for AELtrain = 1.
32 x 10^-8(J). Object to be measured from outer surface 10a
Distance to L_tThen, AELtrain is given by the following equation (5)
Can also be expressed as AELtrain = 1.32 × 10^-8= 3 × 10^-7× (L_Four/ L_t)² ・ ・ ・ (5) L in equation (5)_Four= 3.5 / tan 0.4 = 501m
m. AELtrain = 1.32 x 10 which is the standard value
^-8L to reduce the radiant energy to the value of (J)_tBoundary value of
Is about 2400mm = 2.4m from the formula (5), and the outer surface 1
Satisfies the criteria for Class 1 laser if it is 2.4m away from 0a
You can do it.

AELtrain = 1.32 × 1 on the outer surface 10a
0^-8To meet the Class 1 AEL of (J),
The measurement object is L_t= When the output light intensity is 2.4 m or less,
It is necessary to reduce it to 1/23 or less. Where 1/23 is
3 x 10^-7/1.32 x 10 ^-8It is calculated from 23.
As a member, the reflectance of the dielectric multilayer mirror 35c is
Lumi contact mirror 35b is formed to have a reflectance of 1/23, and L
_t> 2.4 m, the laser diode 21
With the close contact mirror 35b facing the semiconductor laser diode
Reflects the rays of light 21_tWhen <2.4 m, semiconductor
The dielectric multilayer mirror 35c is opposed to the laser diode 21.
And reflect the light beam of the semiconductor laser diode 21.
Good.

The determination of the reflecting surface of the reflecting mirror 33 is controlled according to the flowchart shown in FIG. Step 10
In 1, the semiconductor laser diode 21 irradiates the measured object with one pulse. In step 102, L _t is calculated by the arithmetic circuit mounted on the circuit board 53 based on the equation (2) from the difference between the light receiving time and the light emitting time of the light beam incident on the light receiving element 52 from the measured object through the light receiving lens 51. . If L _t ≦ 2.4 m, the process proceeds to the next step 103, where L _t >.
If 2.4 m, return to step 101 and repeat this routine. In step 103, the semiconductor laser diode 2
By facing the dielectric multilayer film mirror 35c to 1, the emission light density is reduced to 1/23, and the standard of the class 1 laser is cleared from the next one pulse. At this time, one pulse applied to the measured object in step 101 is AELtrain.
Is not satisfied, but AELsingle is satisfied, so there is no problem of radiation exposure. And the next one pulse is AEL
Since the emission intensity satisfies the train, the problem of radiation exposure thereafter does not occur. In step 104, the semiconductor laser diode 21 irradiates the measured object with the next one pulse. Calculate L _t in step 105,
If L _t > 2.4 m, proceed to the next step 106, where L _t ≦
If 2.4 m, return to step 101 and repeat this routine. In step 106, the semiconductor laser diode 21
The aluminum contact mirror 35b is made to face.

FIG. 8 shows the measured distance characteristics in the configuration of the first embodiment. The straight lines 201 to 205 represent the measurable distance range with respect to the scan angle of the light beam. The decrease in the possible measurement distance at wide angles to the left and right is due to the characteristics of the light receiving lens, not the influence of the output system. The reflecting mirror 33 is preferably installed substantially in the middle of the semiconductor laser diode 21 and the collimator lens 40. That is, as in the first embodiment, L
If it is at a position of ₁ = L ₂ = 20 mm, the collimator lens 4
The use of a multifocal lens for 0 does not result in a non-uniform light quantity density distribution of the outgoing light rays that causes a difference in measurement distance.

In the first embodiment, a high-reflectance aluminum contact mirror 35b and a low-reflectance dielectric multilayer mirror 35c are formed on the respective surfaces of the reflecting mirror, and the power of the emitted light is changed by changing the reflecting surface. In the present invention, the method of lowering the current of the semiconductor laser diode to reduce the output of the emitted light beam to a predetermined value, or the method of lowering the current of the semiconductor laser diode to reduce the emission output and the mirror is inverted. It is possible to control the intensity of the emitted light beam by a method of reducing the intensity to a predetermined value in combination with the method.

In the first embodiment, the scanning is performed by reciprocally rotating the reflecting mirror 33, but in the present invention, when the scanning of all angles is completed, the reflecting mirror is returned to the original scanning position at once and then again. A method of starting scanning may be used. (Modification 2) As a modification 2 of the first embodiment, at the following setting values, the measurement accuracy is better than that of the first embodiment.

The same semiconductor laser diode as that of the first embodiment is used. The collimator lens used has a focal length of 43 mm at the center and a diameter of 40 mm, and the half angle of incidence on the collimator lens is 7 °. Distance from the reflecting mirror to the collimator lens and the semiconductor laser diode: 20 mm. The width of the reflecting mirror must be at least 11 mm in order to perform scanning of ± 8 ° under each of these settings.

(Second Embodiment) FIG. 10 shows a reflection measuring apparatus for a vehicle according to a second embodiment of the present invention. In the second embodiment, instead of the step motor of the first embodiment, a DC motor (not shown) is used as the driving means for the reflecting mirror. Since the DC motor always scans the light beam in the same direction, the reflector 33
The projection 37 attached to the photodetector passes between the photointerrupters 38 to detect the angular position of the reflecting mirror 33, and normally, the beam is reflected only by the high-reflectance aluminum contact mirror of the reflecting mirror 33 for scanning. When the object to be measured becomes the distance L _t or less, scanning is performed using only the dielectric multilayer mirror having low reflectance.

Although the DC motor is used as the driving means in the second embodiment, a bimorph actuator may be used in place of the DC motor to scan the light beam emitted from the semiconductor laser diode by the reciprocating motion. is there. (Third Embodiment) FIG. 11 shows a reflection measuring apparatus for a vehicle according to a third embodiment of the present invention.

By forming only the aluminum contact mirror 41a having a high reflectance on the reflecting mirror 41 and inserting and removing the ND filter 42 capable of reducing the power of the light beam emitted from the semiconductor laser diode 21 to a predetermined value. The light quantity density is controlled by adjusting the light quantity of the emitted light beam. The ND filter 42 is not inserted between the semiconductor laser diode 21 and the reflecting mirror 41 when the object to be measured is located farther than the distance L _t , and when the object to be measured is located closer than the distance L _t to the semiconductor laser. The ND filter 42 is inserted between the diode 21 and the reflecting mirror 41.

In the third embodiment, the aluminum contact mirror 41a is used.
Since the surface of is always facing the collimator lens 40,
Since it is possible to perform scanning with the surface of the aluminum contact mirror 41a always overlapping the center of rotation of the rotary table 32, the light quantity density of the light beam irradiated on the object to be measured can be kept uniform. (Fourth Embodiment) FIG. 12 shows a vehicle measuring apparatus according to a fourth embodiment of the present invention.

The fourth embodiment is a semiconductor laser diode 2
Utilizing the fact that the light beam emitted from No. 1 is linearly polarized light, a polarization filter 43 is provided between the semiconductor laser diode 21 and the reflection mirror 41, and the polarization filter 4 is centered on the main axis.
The amount of transmitted light is adjusted by rotating 3 to control the light amount density of the emitted light beam. In the fourth embodiment, the variable amount of the polarization filter 43 is large enough to change the transmitted light amount to zero depending on the rotation angle. Therefore, by increasing the output of the semiconductor laser diode and increasing the distance L _t , rain, fog,
It is possible to cope with a splash or the like due to splashing of water by the preceding vehicle, and it is possible to reduce the light amount when the measured object is within the distance L _t . As a result, the measurable distance can be extended without exceeding the exposure standard.

(Fifth Embodiment) FIG. 13 shows a reflection measuring apparatus for a vehicle according to a fifth embodiment of the present invention. The fifth embodiment is
In this method, a liquid crystal plate 44 is provided between the semiconductor laser diode 21 and the reflecting mirror 41, and the amount of transmitted light is controlled by changing the voltage applied to the liquid crystal plate 44. Also in the fifth embodiment, there is an effect that the measurable distance can be extended without exceeding the exposure standard.

(Sixth Embodiment) FIG. 14 shows a reflection measuring apparatus for a vehicle according to a sixth embodiment of the present invention. The semiconductor laser diode 45 is of a two-beam type, one diode 45a is 40W, and one diode 45b is 10W.
When the measured object is within the distance L _t , the output is switched from 40 W to 10 W.

In the sixth embodiment, the aluminum contact mirror 41a is used.
Is always opposed to the collimator lens 40, so that the surface of the aluminum contact mirror 41a can be scanned with the surface of the rotary table 32 always overlapping, so that the light quantity density of the light beam irradiated on the object to be measured can be made uniform. Can hold (Seventh Embodiment) FIG. 15 shows a reflection measuring apparatus for a vehicle according to a seventh embodiment of the present invention.

When the object to be measured is present farther than the distance L _t, the semiconductor laser diode 2 used in the first embodiment is used.
1, the outer surface 10 of the housing 10 shown in FIG. 7 of the first embodiment is used when the object to be measured is closer than the distance L _t .
A low-power semiconductor laser diode 46 that satisfies the AELtrain in (a) is used. At this time, the reflecting mirror 41 is
The light emitted from the semiconductor laser diode 46 is rotated so that the light is emitted from the collimator lens 40 at a predetermined angle, and the angle can be adjusted.

In the seventh embodiment, the aluminum contact mirror 41a is used.
Is always opposed to the collimator lens 40, so that the surface of the aluminum contact mirror 41a can be scanned with the surface of the rotary table 32 always overlapping, so that the light quantity density of the light beam irradiated on the object to be measured can be made uniform. Can hold In the embodiment of the present invention described above, the reflection measuring device of the present invention was used for measuring the distance, but the present invention is not limited to the distance measuring, and when measuring the angle as the measurement of the relative position of the object. Can also be adopted.

[Brief description of drawings]

FIG. 1 is a plan view showing the inside of a reflection measuring apparatus for a vehicle according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a main part of the first embodiment of the present invention.

FIG. 3 is a plan view showing a reflecting mirror according to the first embodiment of the present invention.

FIG. 4 is a plan view showing a reflecting mirror according to the first embodiment of the present invention.

FIG. 5 is a schematic diagram showing focus characteristics of the collimator lens according to the first example of the present invention.

FIG. 6 is a schematic view showing an irradiation path of light rays according to the first embodiment of the present invention.

FIG. 7 is a control flowchart for switching the reflecting surfaces of the reflecting mirror according to the first embodiment of the present invention.

FIG. 8 is a characteristic diagram showing a measurable range of the vehicle reflection measuring apparatus according to the first embodiment of the present invention.

FIG. 9 is a schematic diagram showing a main part of a first modification of the first embodiment.

FIG. 10 is a schematic diagram showing a main portion of a vehicle reflection measurement apparatus according to a third embodiment of the present invention.

FIG. 11 is a schematic view showing a main part of a reflection measuring apparatus for a vehicle according to a third embodiment of the present invention.

FIG. 12 is a schematic diagram showing a main part of a vehicle reflection measuring apparatus according to a fourth embodiment of the present invention.

FIG. 13 is a schematic diagram showing a main part of a reflection measuring apparatus for a vehicle according to a fifth embodiment of the present invention.

FIG. 14 is a schematic diagram showing a main part of a reflection measuring apparatus for a vehicle according to a sixth embodiment of the present invention.

FIG. 15 is a schematic diagram showing a main part of a reflection measuring apparatus for a vehicle according to a seventh embodiment of the present invention.

FIG. 16 is a schematic view showing a main part of a vehicle reflection measurement apparatus of Conventional Example 1.

FIG. 17 is a schematic diagram showing a main part of a vehicle reflection measurement apparatus of Conventional Example 2.

FIG. 18 is a schematic diagram showing the movement of a reflecting surface of a vehicle reflection measuring apparatus of Conventional Example 2.

FIG. 19 is a schematic diagram showing a positional relationship between an ideal reflecting mirror and an emitting lens.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reflection measuring device 20 Light irradiation part 21 Semiconductor laser diode (light source) 30 Light reflection part 31 Step motor (driving part) 32 Rotating table (driving part) 33 Reflecting mirror (reflecting member) 35 Reflecting mirror main body 40 Collimator lens (emission lens) ) 51 light receiving lens 52 light receiving element (light receiving portion) 53 circuit board (calculation means)

Claims (3)

[Claims] 1. A reflecting member having a first reflecting surface for reflecting a light beam, a driving means for rotating the first reflecting surface of the reflecting member, and an axis of rotation of the reflecting member. A light source provided so that the center of the emitted light ray is reflected, an emission lens that makes the light ray reflected by the first reflection surface substantially parallel light rays, and a light ray that has passed through the emission lens is reflected by the object to be measured,
A light receiving unit that receives the reflected light beam, and a computing unit that calculates the distance to the object to be measured from the difference between the light receiving time at the light receiving unit and the emission time of the light beam emitted from the light source. Reflection measuring device. 2. The reflection measuring apparatus according to claim 1, wherein the distortion curvature of the emission lens increases from the central portion toward the outer peripheral portion. 3. The reflection measuring apparatus according to claim 1, wherein the reflecting member has a second reflecting surface having a reflectance lower than that of the first reflecting surface on the other surface.