JPH0419892Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an imaging device that images an object on an image sensor using a lens.

[Prior art]

As shown in FIG. 5, the imaging device 5, which uses a lens to form an image of a subject on an image sensor made of a solid-state image sensor, etc., has a cylinder 2 equipped with a focus-adjustable lens 1, and an image sensor 3 fixed by a fixture (not shown). It consists of a case 4 with light-shielding properties for storing the case. Image sensor 3 of imaging device 5
In order to obtain a good image of the subject 7 on the element surface, it is necessary to place the subject 7 between the light source 6 and the imaging device 5, and to set the optical axis, adjust the focus, and check the field of view between them. A conventional method for this purpose is to use an oscilloscope or a finder. In the method using an oscilloscope, a video signal obtained by electrically converting the light imaged on the image sensor 3 is imaged on the oscilloscope. This video signal becomes a curve P having a region A where the light amount is reduced due to the shadow of the subject 7, as shown in FIG. 6, in which the vertical axis represents the light amount and the horizontal axis represents the field of view.

[The problem that the idea aims to solve]

However, an oscilloscope has the drawback that it can only tell the amount of light that has entered the image sensor, and cannot see the surroundings.Additionally, the oscilloscope itself is expensive.

On the other hand, the method of using a viewfinder is superior in that it allows observation of a wider range than an oscilloscope, but it requires a complicated optical system and has the drawback of increasing the price of the product.

By the way, as mentioned above, the video signal obtained by an oscilloscope is formed as an image based on the amount of light that enters the image sensor, that is, the brightness and darkness of the light. No longer needed.

However, the case of conventional imaging devices has a structure that can sufficiently block ambient light other than imaging light from entering the image sensor, and structures that may allow ambient light to optically enter the image sensor are avoided. Ta.

[Purpose of invention]

SUMMARY OF THE INVENTION In view of the above-mentioned points, an object of the present invention is to provide an imaging device that has a simple structure and is capable of observing the state of an image formed on an image sensor by a lens.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an imaging device that consists of a tube equipped with a lens and a case housing an image sensor, and in which an image is formed on the image sensor by the lens, from the image sensor to the tube. A peephole was provided in the side wall of the case for observing the image formation state on the surface of the image sensor.

[Effect]

With the above technical means, it is possible to visually observe the image formed on the surface of the image sensor through the peephole and to know the imaging state of the image. This technical means of the present invention is contrary to the common sense in optical equipment, which is to eliminate as much as possible disturbance light from entering the optical system, but according to the experiments of the present inventor, it is possible to use an image sensor with relatively high sensitivity. CCD (Charge Coupled)
Even if it is an image sensor of a device) element, the
If the brightness in a normal room is about lux, and no direct light from the light source enters the image sensor inside the case of the imaging device, even if a peephole is provided on the side wall of the case to observe the surface of the image sensor,
The video signal of the imaging device operated in this state is
10% compared to the saturation output level of the image sensor element
It has been confirmed that there is only a slight increase in background signals and that there is no practical problem in use.

〔Example〕

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

FIG. 1 is a perspective view of an imaging device according to an embodiment of the present invention. In FIG. 1 to FIG. 4, which will be described later, the same parts as in the conventional example shown in FIGS. 5 and 6 are given the same reference numerals. In FIG. 1, the configuration and operation of an imaging device 5 consisting of a tube 2 equipped with a lens 1 and a case 4 housing an image sensor 3 are the same as those of the prior art, and therefore their explanation will be omitted. The difference in this embodiment is that a peephole 8 is provided in the side wall of the case 4 from the position of the image sensor 3 to the cylinder 2, and a light shielding cover 9 that shields the peephole 8 is attached to the peephole 8 by a hinge or the like (not shown). It is attached so that it can rotate around the upper side 10 of the axis.
Note that the optical axis of the lens 1 passes through the element surface of the image sensor 3.

With such a configuration, when the subject 7 is imaged by the imaging device 5, for example, if two objects 7 are placed between the light source 6 and the imaging device 5 as shown in FIG. Two images 7a and 7b as shown in the perspective view of FIG. 3 are focused on the image sensor 3 by the lens 1. Therefore, the images 7a and 7b can be visually observed through the peephole 8 by pulling up the light shielding cover 9 shown in FIG. Therefore, while looking at the images 7a and 7b, the worker must set the optical axis between the lens and the subject, adjust the focus, and check the field of view, that is, check that the images 7a and 7b are correctly focused on the element surface of the image sensor 3. You can check and adjust your field of view.

The light-shielding cover 9 rotates around the side 10 to close the peephole 8 except during the above-mentioned adjustment to prevent disturbance light from entering. As mentioned above, the light-shielding cover does not have a large effect on the imaging by the image sensor 3 at indoor brightness levels, so there is no need to install it.However, at higher brightnesses, the light-shielding cover will affect the imaging. is desirable.

Furthermore, considering the advantage of being able to visually see the image sensor 3, various marks can be provided on the image sensor 3 to facilitate various adjustments. That is, in FIG. 3, an arrow 13 indicating the center position of the element surface 11 covered with the protective glass 12 and an indication 14 indicating the effective range of the element surface 11 can be marked on the surface of the image sensor 3. Furthermore, as shown in FIG. 4, by placing a screen 15 depicting the shape 16 of the element surface 11 of the image sensor 3 on the image sensor 3 so as to match the shape of the element surface 11, the object 7 can be seen on the screen 15. The image is more clearly imaged than the surface of the image sensor 3, making it easier to observe. After observing and completing various adjustments, the screen 15 can be removed.

In addition, when observing the image on the image sensor through the above-mentioned peephole, in an imaging device using a relatively high-sensitivity image sensor such as an image pickup tube, it is necessary to prevent image burn-in due to disturbance light entering the image sensor element. Therefore, it is necessary to keep the image sensor elements in a non-operating state. However, if an imaging device uses an image sensor with lower sensitivity than an image sensor made of a CCD element, it is possible to operate the imaging device and observe a video signal while observing an image formed on the image sensor. In addition,
The peephole should be located anywhere in the case from the image sensor to the tube, as long as it is not directly exposed to light from a light source, etc., and the element surface can be observed when observing through the peephole. It's good. This is because the image on the image sensor can be seen clearly because light is normally blocked by the head of the viewer during observation.

[Effect of idea]

As is clear from the above explanation, according to the present invention, by providing a peephole in the case of the imaging device, it is possible to observe the image of the subject that is formed on the image sensor through the peephole, so that the image is correctly displayed on the image sensor. It can be easily adjusted to be tied to the upper element surface. Note that since this observation can be performed using a simple structure such as a peephole, there is also the effect that manufacturing costs are reduced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an imaging device according to an embodiment of the present invention, FIG. 2 is a layout diagram for imaging a subject using the imaging device shown in FIG. 1, and FIG. 4 is a perspective view of a screen arranged on the image sensor of the imaging device shown in FIG. 1, FIG. 3 is a graph showing the state of a video signal applied to an element of the image sensor shown in the figure. 1... Lens, 2... Tube, 3... Image sensor, 4... Case, 8... Peephole.

Claims (1)

[Claims for Utility Model Registration] An imaging device comprising a tube provided with a lens and a case housing an image sensor, the imaging device forming an image on the image sensor using the lens, comprising: An imaging device characterized in that a peephole is provided in a side wall of the case for observing an imaging state on the surface of the image sensor.