JPH0560736B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electronic endoscope, and more specifically, to an electronic endoscope whose distal end can have a reduced outer diameter.

[Prior Art] In an electronic endoscope, an optical signal related to an image obtained through an objective lens is converted into an electrical signal inside the distal end inserted into the object to be observed.
An imaging means assembly is housed therein for sending this to a processor and playing it back as it is or recording it as an image.

In the conventional imaging means assembly, as shown in FIGS. 4 to 6, the entrance surface of a rectangular prism 2 is disposed orthogonal to the optical axis of the objective lens group 1, and the exit surface 21 of the rectangular prism 2 is arranged perpendicularly to the optical axis of the objective lens group 1. A solid-state image sensor 4, such as a CCD, is provided downward in surface contact (therefore, the exit surface 21 of the right-angle prism 2 and the cover glass 41 of the solid-state image sensor 4 are in contact). A connection board 3, which is a printed circuit board on which electronic components such as a transistor 6 and a capacitor 7 are mounted, is provided below the solid-state imaging device 4, and supports each of the above-mentioned imaging means, forming the entire imaging means. It is put together as an assembly. In addition, the code 9, 9
indicates a light guide hole.

[Problem to be solved by the invention]

Conventionally, the connection board 3 first connects the solid-state image sensor 4.
This is because the structure is positioned below and supports the second solid-state image sensor 4, and the connection between the lead wire extending from the electrode plate surface of the second solid-state image sensor 4, that is, the surface where the cover glass 41 is provided, and the connection substrate 3 is made. The width W ₁ is smaller than that of the solid-state image sensor for two reasons: the connecting portion 5 is attached around the outermost edge of the imaging means assembly, and this makes it susceptible to mechanical damage. 4 in the same direction. Therefore, the width of the imaging means assembly is effectively defined by the width W ₁ of this connection board 3, and the inner diameter of the endoscope tip is selected to accommodate this width W ₁ .

Furthermore, since the electronic components such as the transistor 6 and the capacitor 7 mounted on the connection board 3 are mounted on the opposite side where the solid-state image sensor 4 contacts, that is, the bottom surface of the connection board in FIG. Hole 1
0, the forceps hole 11, etc., consideration is also taken into consideration when selecting the inner diameter of the tip.

As can be seen from the above explanation, the diameter of the tip of the endoscope is determined based on the width of the solid-state image sensor 4.
From this, the width of the connection board 3 that is wide enough to accommodate the space provided with the connection wiring section 5 is determined, and the electronic components mounted on the connection board 3 are determined based on the conditions that they do not interfere with the various conductive holes. Even if we tried to make the diameter of the tip of the endoscope as small as possible, we could not overcome the basic constraint of the width of the solid-state image sensor, and no great results could be expected.

[Means to solve the problem]

The present invention was made in order to solve the above-mentioned problem, and includes an objective lens group, a right-angle prism provided with an incident surface perpendicular to the optical axis of the objective lens group, and an exit surface of the right-angle prism. In an electronic endoscope, the electronic endoscope includes an imaging means assembly including a solid-state imaging device disposed in surface contact with the solid-state imaging device, and a connection board for sending an image signal obtained by the solid-state imaging device to a processor. A notch corresponding to the output surface of the right-angle prism is formed in the substrate, so that the connection substrate is on the side of the right-angle prism with respect to the solid-state image sensor and is on the surface of the cover glass of the solid-state image sensor. It is provided so that it makes surface contact.

[Effect]

Since the connection board is located on the side of the right-angle prism relative to the solid-state image sensor, the desired connection portion can be formed by making the connection board smaller than the width of the solid-state image sensor. By matching the emission surfaces of the two, surface contact can be made with the solid-state image sensor.

[Embodiment] An embodiment of the present invention will be described with reference to FIGS. 1 to 3. Figures 4 to 6 are indicated by the numbers in the figure.
The same reference numerals as used for the prior art in the figures refer to the same elements.

The right-angle prism 2 is arranged so that its entrance plane is orthogonal to the optical axis of the objective lens group 1. on the other hand,
Connection board 3 having a width W narrower than the solid-state image sensor 4
is disposed so as to be surface-connected to the surface of the solid-state image sensor 4, that is, the cover glass surface 41, and the connecting wire portion 5 that connects the two is located outside the side edge of the connection board 3, and furthermore, is connected to the surface of the solid-state image sensor 4. It is located inside the side edge. The output surface 21 of the right-angle prism 2 passes through the notch 31 of the connection board 3 to the solid-state image sensor 4.
, that is, the surface of the cover glass 41 .

To rewrite the arrangement order of each of the above-mentioned components, from the top in FIG. Note that the connecting board 3 is now next to the rectangular prism 2. What allows the exit surface 21 of the right-angle prism 2 to come into contact with the solid-state image sensor 4 even in this arrangement is, of course, the notch 31 formed in the connection substrate 3.

Note that the transistor 6 and the capacitor 7 are attached to the connection substrate 3 on the right angle prism 2 side. Further, reference numeral 8 is a connection cable that sends the image signal converted in the solid-state image sensor 4 to a processor (not shown).

〔effect〕

According to this invention, (1) since a connection substrate having a width narrower than that of the solid-state image sensor is used, the maximum width of the imaging means assembly is determined by that of the solid-state image sensor; The diameter of the endoscope tip can be reduced. In addition, since there is space for mounting electronic components on the surface of the connection board on the right-angle prism side, there is a risk of interference with the air and water supply holes and forceps holes, unlike conventional cases where electronic components are mounted on the surface opposite to the right-angle prism. This has the effect of helping to reduce the tip diameter without having to do so.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a plan view as seen from the right angle prism side, FIG. 3 is a cross-sectional view, and FIGS. 4, 5, and 6 are They are a perspective view, a plan view viewed from the right-angle prism side, and a cross-sectional view, respectively, in the prior art. 1...Objective lens group, 2...Right angle prism, 3
...Connection board, 4...Solid-state image sensor, 31...
Notches, 6, 7...Electronic components.

Claims (1)

[Scope of Claims] 1. An objective lens group 1, a right-angle prism 2 provided with an incident surface perpendicular to the optical axis of the objective lens group, and a right-angle prism 2 arranged so as to be in surface contact with an exit surface 21 of the right-angle prism. In an electronic endoscope having an imaging means assembly including a solid-state imaging device 4 and a connection board 3 for sending an image signal obtained by the solid-state imaging device to a processor, the connection board 3
A notch 31 corresponding to the output surface of the right-angle prism is formed in the right-angle prism, so that the connection substrate is on the side of the right-angle prism with respect to the solid-state image sensor 4, and the cover glass 41 of the solid-state image sensor is An electronic endoscope characterized in that it is provided so as to be in surface contact with a surface. 2 electronic components 6 mounted on the connection board 3;
2. The electronic endoscope according to claim 1, wherein a part or all of 7 is attached to a surface on the right angle prism 2 side with respect to the solid-state image sensor 4.