JPH08262204A - Integrally molded lens - Google Patents

Abstract

PURPOSE: To easily and surely decrease the stray light from a first lens to second lens integrally molded to a main body member of an integrally molded lens formed by integrally molding the plural lenses to the main body member consisting of a resin, etc. CONSTITUTION: This integrally molded lens is constituted by integrally molding the first lens 15a and the second lens 15b apart a prescribed spacing to the main body member 15 and arranging a light shielding means or light scattering means for shielding or scattering the stray light from the first lens 15a to the second lens 15b between the first lens 15a and the second lens 15b. The light shielding means is formed by a light shielding member 23 insert molded between the first lens 15a and the second lens 15b. Further, the light scattering means is formed by a slit formed between the first lens 15a and the second lens 15b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrally molded lens formed by integrally molding a plurality of lenses on a body member made of resin or the like.

[0002]

2. Description of the Related Art Conventionally, in devices such as cameras, there has been known a distance measuring device for calculating the distance to an object by the round trip time of pulsed light. Conventionally, an optical system of this type of distance measuring device is, for example, a light-transmitting lens for transmitting infrared pulsed light to an object, a light-receiving lens for receiving reflected light from the object, and other than measurement light. It is composed of an infrared transmission filter that transmits only infrared pulsed light in order to cut the wavelength.

Recently, it is known that the light receiving lens is formed of an infrared light transmitting resin that transmits only infrared pulse light, the infrared transmitting filter is eliminated, and the number of parts is reduced. On the other hand, recently, although it is not a publicly known technology,
As shown in FIG. 6, the present inventor integrally molds the light-transmitting lens 1a and the light-receiving lens 1b at a predetermined interval on the main body member 1 made of, for example, an infrared light transmissive resin, and the number of parts and the assembly We are trying to reduce man-hours.

[0004]

However, in such an integrally molded lens, since the light transmitting lens 1a and the light receiving lens 1b are integrally molded on the main body member 1 made of an infrared light transmitting resin, the lens 1a is formed. , 1b have the same refractive index as the lenses 1a, 1b, and a part of the infrared pulsed light 3 emitted from the light emitting element 2 has a light transmitting lens 1a and a light receiving lens 1a as shown by the dotted line in the figure. The back surface is repeatedly reflected in the inside of 1b to become stray light, which enters the light receiving element 5 as noise light 4 and causes a problem of reducing the S / N ratio of the distance measuring device.

The present invention has been made in consideration of such circumstances, and an integrally formed lens capable of easily and surely reducing stray light from the first lens integrally formed on the main body member to the second lens. The purpose is to provide.

[0006]

The integrally molded lens according to claim 1, wherein the body member includes a first lens and a second lens,
It is integrally molded at a predetermined interval, and a light blocking unit for blocking stray light from the first lens to the second lens is arranged between the first lens and the second lens. Characterize.

According to a second aspect of the present invention, there is provided the integrally molded lens according to the first aspect, wherein the light shielding means is a light shielding member which is insert-molded between the first lens and the second lens. The integrally molded lens according to claim 3, wherein the first lens and the second lens are integrally molded on the main body member at a predetermined interval, and between the first lens and the second lens, It is characterized in that a light scattering means for scattering stray light from the first lens to the second lens is arranged.

According to a fourth aspect of the present invention, there is provided the integrally molded lens according to the third aspect, wherein the light scattering means is a slit formed between the first lens and the second lens. According to a fifth aspect of the present invention, in the integrally molded lens according to the fourth aspect, the inner surface of the slit is a rough surface. According to a sixth aspect of the present invention, there is provided the integrally-molded lens according to the third aspect, wherein the light-scattering means comprises an unevenness formed on a surface of a main body member between the first lens and the second lens. .

According to a seventh aspect of the present invention, there is provided an integrally molded lens according to the first to sixth aspects, wherein the first lens is a light-sending lens that sends light from a light emitting element to an object, and the second lens is the light-transmitting lens. It is a light-receiving lens that guides reflected light from an object to a light-receiving element. According to an eighth aspect of the present invention, there is provided the integrally molded lens according to the first to seventh aspects, wherein the main body member is made of an infrared light transmitting resin.

According to a ninth aspect of the present invention, there is provided the integrally molded lens according to the first to eighth aspects, wherein the main body member is a housing of a device.

[0011]

In the integrally-formed lens according to the first aspect, the stray light from the first lens to the second lens is blocked by the light blocking means arranged between the first lens and the second lens, and the second lens is blocked.
Stray light does not enter the lens.

In the integrally molded lens of claim 2, stray light from the first lens to the second lens is blocked by the light blocking member insert-molded between the first lens and the second lens, Stray light does not enter the second lens. In the integrally molded lens according to claim 3, stray light from the first lens to the second lens is scattered by the light scattering means arranged between the first lens and the second lens, and the second lens Penetration of stray light into the space is reduced.

In the integrally molded lens according to claim 4, stray light from the first lens to the second lens is scattered by the slit formed between the first lens and the second lens, and the second lens is scattered. Penetration of stray light into the lens is reduced. In the integrally molded lens of claim 5, since the inner surface of the slit is roughened, stray light from the first lens to the second lens is more surely scattered.

In the integrally molded lens according to claim 6, stray light from the first lens to the second lens is scattered due to the unevenness formed on the surface of the main body member between the first lens and the second lens. As a result, the invasion of stray light into the second lens is reduced. In the integrally molded lens of the seventh aspect, the light transmitting lens that sends the light from the light emitting element to the object and the light receiving lens that guides the reflected light from the object to the light receiving element are integrally formed on the main body member.

In the integrally molded lens according to claim 8, the main body member, the first lens and the second lens are formed of an infrared light transmitting resin which transmits only infrared light. In the integrally molded lens according to claim 9, the housing of the device is directly used as the main body member.

[0016]

Embodiments of the present invention will now be described in detail with reference to the drawings.

1 and 2 show a first embodiment of the integrally molded lens of the present invention, which is used in a distance measuring device. In this distance measuring device, the infrared pulsed light 13 from the light emitting element 11
Is transmitted to an object (not shown) by a light transmitting lens 15a formed on the main body member 15, and reflected light 17 from the object is transmitted.
Are guided to the light receiving element 19 by the light receiving lens 15b.

Then, the distance calculation device 21 calculates the distance to the object based on the round trip time until the light receiving element 19 receives the infrared pulsed light 13 sent from the light emitting element 11. The integrally-molded lens of this embodiment is formed by integrally molding a light-transmitting lens 15a and a light-receiving lens 15b on a main body member 15 having a rectangular plate shape at predetermined intervals.

The body member 15 and the light transmitting lens 15
The light receiving lens 15b is integrally formed of an infrared light transmitting resin that transmits only infrared light. Light transmitting lens 15
A long light shielding member 23 made of, for example, aluminum is embedded between the a and the light receiving lens 15b by insert molding.

A concave portion 23a is formed in the light shielding member 23 to prevent the light shielding member 23 from coming off from the main body member 15.
A connection projection 15c is formed on the rear side of the light shielding member 23 of the main body member 15, and connection portions 15d are formed on both sides of the main body member 15 in the axial direction of the light shielding member 23.

In the integrally molded lens configured as described above, the light transmitting lens 15 is formed by the light shielding member 23 which is insert-molded between the light transmitting lens 15a and the light receiving lens 15b.
Stray light from a to the light receiving lens 15b is blocked, and stray light does not enter the light receiving lens 15b.
From the light-transmitting lens 15a integrally molded to the light-receiving lens 15
Stray light to b can be easily and surely eliminated.

Then, the light transmitting lens 15a and the light receiving lens 1
Since 5b and 5b are resin-molded on the main body member 15, it is not necessary to adjust the mutual position of the light transmitting lens 15a and the light receiving lens 15b, and the number of assembly and adjustment steps can be reduced. In addition, the light blocking member 23 is connected to the light transmitting lens 15a and the light receiving lens 15
Since it is arranged by insert molding with b, the light shielding member 23 can be easily and surely incorporated into the main body member 15 at the time of injection molding, and the productivity can be improved.

Further, in the above-mentioned integrally molded lens, the light transmitting lens 15a for sending the infrared pulsed light 13 from the light emitting element 11 to the object and the light receiving lens 15b for guiding the reflected light 17 from the object to the light receiving element 19 are provided. Since it is integrally formed with the main body member 15, a lens for the distance measuring device can be easily obtained. When used in a distance measuring device, stray light from the light-transmitting lens 15a integrally molded with the main body member 15 to the light-receiving lens 15b is eliminated, so that the stray light does not enter the light-receiving element 19 as noise light.
It is possible to prevent the S / N ratio of the distance measuring device from decreasing.

Further, in the above-mentioned integrally molded lens, since the main body member 15, the light transmitting lens 15a and the light receiving lens 15b are formed of an infrared light transmitting resin which transmits only infrared light, an infrared light transmitting filter is used. It is not necessary to arrange the optical system in the optical system, and the optical system can be simplified. FIGS. 3 and 4 show a second embodiment of the integrally molded lens of the present invention. The parts having the same functions as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, a long slit 15e which is a light diffusing means is formed between the light transmitting lens 15a and the light receiving lens 15b of the main body member 15. Then, the connection portions 15d are formed on both sides of the main body member 15 in the axial direction of the light shielding member 23. In this example,
The slit 15e formed between the light-transmitting lens 15a and the light-receiving lens 15b scatters stray light from the light-transmitting lens 15a to the light-receiving lens 15b and reduces stray light from entering the light-receiving lens 15b. Stray light from the light-transmitting lens 15a integrally formed with the light-receiving lens 15 to the light-receiving lens 15b can be easily and surely reduced.

Further, for example, by forming a convex portion corresponding to the slit 15e in a mold for injection molding, the slit 15e can be easily and surely formed. In addition,
In this embodiment, the inner surface 15f of the slit 15e is
The light-transmitting lens 15 has a rough surface with a large surface roughness.
Stray light from a to the light receiving lens 15b can be more reliably scattered.

FIG. 5 shows a third embodiment of the integrally molded lens of the present invention. The parts having the same functions as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In this example,
A large number of protrusions 15g are integrally formed on the surface of the main body member 15 between the light transmitting lens 15a and the light receiving lens 15b, thereby forming irregularities as light diffusing means.

In this embodiment, due to the unevenness formed by the projection 15g, the light transmitting lens 15a to the light receiving lens 15 are formed.
Since stray light to b is scattered and invasion of stray light to the light receiving lens 15b is reduced, stray light from the light transmitting lens 15a integrally formed on the main body member 15 to the light receiving lens 15b can be easily performed.
It can be surely reduced. Further, for example, by forming a recess corresponding to the protrusion 15g in the injection molding die, the protrusion 15g can be formed easily and reliably.

In the above embodiment, the main body member 15
However, the present invention is not limited to such an example, and the main body member can be directly used as a housing of the device or the like to provide a housing of the device or the like. Since it is not necessary to assemble the main body member, the number of assembling steps can be reduced. Further, in the above-described embodiment, the example in which the light shielding member 23 is formed of aluminum has been described, but the present invention is not limited to such an embodiment, and the light shielding member may be formed of a resin that does not transmit light. good.

Furthermore, in the above-mentioned embodiments, an example in which the integrally molded lens of the present invention is used in a distance measuring device has been described, but the present invention is not limited to such embodiments, and various optical systems are used. Can be widely applied to.

[0031]

According to the integrally molded lens of claim 1, stray light from the first lens to the second lens is shielded by the light shielding means arranged between the first lens and the second lens. Since stray light does not enter the second lens, stray light from the first lens integrally molded with the main body member to the second lens can be easily and surely eliminated.

In the integrally molded lens of claim 2, stray light from the first lens to the second lens is blocked by the light blocking member that is insert-molded between the first lens and the second lens, Since stray light does not enter the second lens, stray light from the first lens integrally molded with the main body member to the second lens can be easily and surely eliminated.

Further, since the light blocking member is arranged by insert molding between the first lens and the second lens, the light blocking member can be easily and surely incorporated into the main body member at the time of injection molding. Can be improved. In the integrally molded lens according to claim 3, stray light from the first lens to the second lens is scattered by the light scattering means arranged between the first lens and the second lens, and the second lens Since the invasion of stray light into the main body member is reduced, it is possible to easily and reliably reduce the stray light from the first lens integrally molded with the main body member to the second lens.

In the integrally-molded lens of claim 4, stray light from the first lens to the second lens is scattered by the slit formed between the first lens and the second lens, and the second lens is scattered. Since the invasion of stray light into the lens is reduced, it is possible to easily and surely reduce the stray light from the first lens integrally molded with the main body member to the second lens. Also,
By forming the convex part corresponding to the slit in the mold,
The slit can be formed easily and surely.

In the integrally molded lens of the fifth aspect, since the inner surface of the slit is roughened, stray light from the first lens to the second lens can be more surely scattered. In the integrally molded lens according to claim 6, stray light from the first lens to the second lens is scattered by the unevenness formed on the surface of the main body member between the first lens and the second lens, Two
Since the invasion of stray light into the lens is reduced, the stray light from the first lens integrally molded with the main body member to the second lens can be easily and surely reduced.

In the integrally molded lens of claim 7, the light-sending lens for sending the light from the light-emitting element to the object and the light-receiving lens for guiding the reflected light from the object to the light-receiving element are integrally formed on the main body member. Therefore, the lens for the distance measuring device can be easily obtained. In addition, since there is no stray light from the first lens integrally molded to the main body member to the second lens, the stray light does not enter the light receiving element as noise light,
It is possible to prevent the S / N ratio of the distance measuring device from decreasing.

In the integrally molded lens according to claim 8, since the main body member, the first lens, and the second lens are formed of an infrared light transmitting resin that transmits only infrared light, the infrared light transmitting filter is formed. It is not necessary to arrange the optical system in the optical system, and the optical system can be simplified. In the integrally molded lens according to claim 9, since the housing of the device or the like is used as the main body member as it is,
There is no need to assemble the main body member to the housing of equipment,
There is an advantage that the number of assembling steps can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example in which a first embodiment of an integrally molded lens of the present invention is used in a distance measuring device.

2 is a front view showing the integrally molded lens of FIG. 1. FIG.

FIG. 3 is a cross-sectional view showing a second embodiment of the integrally molded lens of the present invention.

FIG. 4 is a front view showing the integrally molded lens of FIG.

FIG. 5 is a cross-sectional view showing a third embodiment of the integrally molded lens of the present invention.

FIG. 6 is an explanatory diagram showing a distance measuring device developed by the present inventor.

[Explanation of symbols]

 11 Light emitting element 15 Main body member 15a Light transmitting lens 15b Light receiving lens 15e Slit 15f Inner surface 15g Protrusion 19 Light receiving element 23 Light blocking member

Claims (9)

[Claims] 1. A first lens and a second lens are integrally molded on a main body member at a predetermined interval, and the first lens and the second lens are formed between the first lens and the second lens. An integrally molded lens, characterized in that a light blocking means for blocking stray light from the lens to the second lens is arranged. 2. The integrally molded lens according to claim 1, wherein the light shielding unit is a light shielding member that is insert-molded between the first lens and the second lens. . 3. A first lens and a second lens are integrally formed on a main body member at a predetermined interval, and the first lens and the second lens are formed between the first lens and the second lens. An integrally molded lens, wherein a light scattering means for scattering stray light from the lens to the second lens is arranged. 4. The integrally formed lens according to claim 3, wherein the light scattering means is a slit formed between the first lens and the second lens. 5. The integrally formed lens according to claim 4, wherein the inner surface of the slit is a rough surface. 6. The integrally-molded lens according to claim 3, wherein the light scattering means comprises unevenness formed on the surface of the main body member between the first lens and the second lens. Integral molded lens. 7. The integrally molded lens according to claim 1, wherein the first lens is a light transmitting lens that sends light from a light emitting element to an object, and the second lens. Is a light-receiving lens that guides reflected light from the object to a light-receiving element. 8. The integrally molded lens according to claim 1, wherein the main body member is made of infrared light transmissive resin. 9. The integrally molded lens according to claim 1, wherein the main body member is a housing of a device.