JP3066490B2 - Infrared detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared detector which is provided in a device used in a high impact and high rotation environment and requires precise optical axis alignment.

[0002]

2. Description of the Related Art When there is an object that strongly radiates infrared light on a scanning line of the infrared detection device, the infrared light radiated from the object is detected by the infrared detection device, whereby the infrared detection device recognizes the position of the object. Can be. However, in order to accurately measure the position of the object, the accuracy of the optical axis of the infrared detection device is extremely important. However, in infrared detectors that have received (or are receiving) high impact and high rotation,
The optical axis of the optical system provided inside is shifted. When the optical axis shift occurs, the infrared detecting device recognizes that the object is located within the field of view of the infrared detecting device, and erroneously detects the actual position of the object. Here, an infrared detector that does not cause a problem of optical axis deviation even in such a high impact and high rotation environment will be described below.

FIG. 2 is a plan view and a sectional view showing the structure of a conventional infrared detector for high impact and high rotation. In this figure, reference numeral 6 denotes a condensing lens, which has a convex upper surface and a concave lower surface. Reference numeral 7 denotes an adapter for holding the lens 6, which has a hollow cylindrical shape, and has a plurality of steps on the inner peripheral wall. The lens 6 is placed on the upper step 7a and fixed by the annular ring 10. Reference numeral 8 denotes a photodiode for detecting infrared light condensed by the lens 6, which is attached to the focal point of the lens 6. 9
Is a signal processing circuit for processing the output signal of the photodiode 8.

In such a configuration, the adjustment of the optical axis is performed by providing a gap 11 between the lens 6 and the adapter 7 and moving the lens 6 left and right in the gap 11.

[0005]

In the above-mentioned conventional infrared detector for high impact and high rotation, the lens 6 may move due to high impact and high rotation, and the optical axis may be out of order. there were. When a high impact is applied, the lens 6
Since a large impact is applied to the lower edge, there is a problem that the lens 6 is easily damaged. The present invention has been made under such a background, and even when high impact and high rotation are applied, the optical axis does not become out of order, and the adjustment process of the optical axis is unnecessary. It is another object of the present invention to provide an infrared detection device that does not have a risk of damaging a lens.

[0006]

[MEANS FOR SOLVING THE PROBLEMS]
In an infrared detection device placed in a high impact and high rotation environment, a lens 12 formed on a substantially conical tapered surface that condenses infrared light, has a circular upper part of the side surface and a smaller inner diameter as going downward, A substantially conical tapered surface is formed on the inside where the upper portion of the lens 12 where the tapered surface engages is circular and the inner diameter decreases as going downward, so that the lens 12 can be attached to the adapter 13 even when high impact and high rotation are applied. An adapter 13 for holding the lens 12 by the tapered surface and the annular member so as not to be displaced in the inside; an annular member for locking a peripheral portion of a light receiving surface of the lens 12 in the adapter 13; Photoelectric conversion means for converting the infrared light condensed by the light into an electric signal. A small hole 13b and a large hole 13c are sequentially formed below the tapered surface in the adapter 13, and a photodiode 8 for detecting infrared light collected by the lens 12 is mounted in the small hole 13b. A signal processing circuit 9 for processing the output of the photodiode 8 is mounted in the large hole 13c.

According to the present invention, since the tapered surface formed on the lens and the tapered surface formed on the adapter are engaged, the lens may be displaced in the adapter even when high impact and high rotation are applied. Without this,
There is no possibility that the optical axis of the lens is shifted. Further, since the lens is received on the adapter surface, unlike a conventional lens which receives the lens with a wire, the lens is not easily damaged even when subjected to high impact and high rotation.

[0008]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the configuration of one embodiment of the present invention. In this figure, reference numeral 12 denotes a lens for condensing infrared rays. The upper surface is formed as a convex surface, the lower surface is formed as a concave surface, and the side surface is formed as a tapered surface 12a. 1
Reference numeral 3 denotes an aluminum adapter for holding the lens 12, and has a substantially frusto-conical tapered surface 13a in which the upper portion is circular and the inner diameter decreases as going downward. The inclination angle of the tapered surface 13a matches the inclination angle of the tapered surface 12a of the lens 12.
Is the tapered surface 12a of the adapter 13
Is set in the adapter 13 in a state of being engaged. In this case, the tapered surface 12a of the lens 12 and the adapter 13;
The inclination angle of 13a is set in advance according to the magnitude of the magnitude of the impact / rotation applied to the optical lens 12. Below the taper 13a, a small hole 13b, a large hole 13
c are sequentially formed, and a photodiode 8 for detecting infrared light collected by the lens 12 in the small hole 13b
A signal processing circuit 9 for processing the output of the photodiode 8 is mounted in the large hole 13c with a screw 16. Further, a metal ring 14 for holding down the lens 12 from above and fixing the lens 12 through a semi-hard packing 15 is attached to the upper part of the adapter 13.

In such a configuration, the lens 12 and the adapter 13 are formed in advance with taper angles 12a and 13a so that the optical axis and the focal point are in focus with the photodiode 8. When assembling the optical system, the lens 12 is attached to the adapter 12. 13 into the tapered surface 13a of the hollow portion of the lens 13 and the lens 1
The upper part 2 may be fixed with the metal ring 14 and the packing 15. Once the optical system is assembled, there is no need to adjust the optical axis at all, and the optical axis does not shift even when subjected to high impact and high rotation.

[0010]

As described above, according to the present invention,
Since the tapered surface formed on the lens and the tapered surface formed on the adapter are engaged with each other, even when high impact and high rotation are applied, there is no risk that the lens will be displaced in the adapter. There is no danger that the shaft will shift. Also, since the lens is received on the adapter surface, unlike a conventional lens which receives the lens with a wire, the lens is not easily damaged even if an impact is applied.

[Brief description of the drawings]

FIG. 1 is a plan view and a cross-sectional view illustrating a configuration of an infrared detection device according to an embodiment of the present invention.

FIG. 2 is a plan view and a cross-sectional view illustrating a configuration of a conventional infrared detection device.

[Explanation of symbols]

 8 Photodiode 9 Signal processing circuit 12 Lens 13 Adapter 14 Metal ring 15 Packing

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-204333 (JP, A) JP-A-60-213916 (JP, A) JP-A-63-148212 (JP, A) JP-A-1- 224629 (JP, A) JP-A-7-209567 (JP, A) JP-A 62-49116 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01J 1/02-1 / 06 G01J 5/02 G01V 9/04 G02B 7/00-7/02 G04B 13/19-13/191

Claims (1)

(57) [Claims] 1. An infrared detecting device which is placed in an environment of high impact and high rotation. The infrared detecting device is formed on a substantially conical tapered surface which converges infrared light and has a circular upper part of a side surface and an inner diameter which becomes smaller as going downward. The lens has a substantially conical tapered surface in which the upper portion where the tapered surface of the lens engages is circular and the inner diameter decreases as going downward, and the lens is formed even when high impact and high rotation are applied. An adapter for holding the lens by the tapered surface and the annular member so as not to be displaced in the adapter; an annular member for locking a peripheral portion of a light receiving surface of the lens in the adapter; Photoelectric conversion means for converting infrared light into an electric signal, wherein a small hole is provided below the tapered surface in the adapter.
And a large hole are formed sequentially, and the small hole
A photodiode that detects the collected infrared light is installed
And the output of the photodiode is processed in the large hole.
An infrared detection device, comprising a signal processing circuit that performs the operation .