DE1886062U - VIEWING DEVICE FOR X-RAY IMAGE AMPLIFIER. - Google Patents

Description

RA. 758 056 * 11/25/63

N.V. Optical industry "De Oude DeKt" in Deift (Netherlands)

Viewing device for X-ray image intensifiers

The innovation relates to a periscope-like one

Viewing device for X-ray image intensifiers, which device besides the imaging optical elements such as one or more lenses and one eyepiece at least contains four planar, reflective surfaces which bend the optical axis of the device in such a way that the exit pupil of the device is closer to the patient than the screen of the image intensifier tube and the Direction of view is directed towards the patient, with an upright image of the primary X-ray image is observable »Such a device is in the patent literature known.

In the case of facilities of the type mentioned, a complete Erecting the image is desirable, so that the spatial position

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that observed by means of the observation device The passage image always corresponds to the actual position of the patient, so that orientation is made easier for the examining doctor.

The mentioned system of reflective surfaces in the task of the viewing device is to provide the required Bring about bending of the optical axis. But it should also, if necessary in combination with special Elements to be arranged for this purpose, such as image-rotating prisms, be designed in such a way that the apparatus as a G; provides an upright fluoroscopic image.

In the known device, an image intensifier is used used without pre-optics, in which the viewing device only has a single lens. The imaging elements of the image intensifier and the viewing device together call an even number of image inversions of the primary X-ray. The four plane mirrors are up set up in such a way that all parts of the four folds optical axis lie in one and the same plane. It is easy to see that there is a The image is reversed four times by the mirrors and is consequently shown upright. On a picture perpendicular to the The mirrors have no optical axis plane at all Influence.

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The present innovation is characterized in that the imaging elements of the image intensifier and the observation device together an odd number by generating image inversions of the primary X-ray image and the four flat, reflective surfaces are arranged in the manner of a Porro prism set of the first type are.

The structure of a Porro * prism system of the first kind is well known and needs no special description. For example, refer to Naumann's book "Optik for constructors ", pp. 71-72.

An odd number of reversals by the imaging Elements can be created, for example, by using an image intensifier with a pre-optic. Included a free-standing fluorescent screen is used as the receiver of the X-rays, from which a lens is attached inverted, reduced image on the photocathode of the Image intensifier tube designs. Another cause may be that in order to enlarge the aperture of the wiring device, the latter with two connected in series Lenses. One of these lenses is placed close to the screen of the image intensifier and designs an intermediate image that is imaged in the focal plane of an eyepiece by means of the second objective.

The advantage of the observation device according to the The innovation is that the four to turn the beam

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lenganges required reflective surfaces in that they are in the manner of a Porrof prism system are arranged first type, also provide the desired image erection, so that the arrangement additional Aids, such as image-rotating prisms, or the replacement of * reflective surfaces with more complex ones Elements such as roof prisms, penta prisms or the like are unnecessary. Because the elements mentioned of a greater accuracy require in terms of material, manufacture and adjustment, the invention enables substantial savings.

The innovation is explained on the basis of the accompanying drawing, which shows an image intensifier that works with the viewing device « after the innovation is provided.

Fig. 1 shows a perspective view of the device with parts of the housing for better illustration the optical parts located therein broken away are.

Fig. 2 is a top plan view of the device of Fig. 1 _.:

An X-ray image intensifier tube 2 is located in the housing 1 housed, the Bildsdbirm 3 a brightly shining, reduced and reverse image of the primary x-ray silhouette supplies. The reduced image can be evaluated in various ways. In the drawing is above the image intensifier a bright lens consisting of two equal parts 4 and 5 is shown, which shows the image in relation to each other

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1: 1 on a film strip (not shown) or on projected the light-sensitive receiving plate of a television camera. The picture can also be visual at the same time be observed by means of a magnifying viewing device, so that a direct fluoroscopy, if necessary in combination with the photographic definition of the image, is possible. In the parallel beam path between the objective parts 4 and 5, for example, a semi-transparent plane mirror 7 is at an angle of 45 ° to arranged optical axis. This mirror throws part of the light beam in a direction perpendicular to the optical axis to the outside, where the rays are captured by an objective 9. The lens 9 is held in a tube 8, which is attached to a ring 6 which engages around the upper cylindrical part of the housing 1 and relative to the housing is rotatable. The tube 8 forms the first horizontal part of the multiple kinked housing of the viewing device. This consists of a vertical pipe section 12, a horizontal pipe section 15, which crosses the pipe 8 vertically, a slightly inclined to the vertical axis pipe section 17 and a prism housing 19. The plane mirror 7 is through a socket, not shown, is connected to the ring 6 and is connected to the latter and the entire viewing device rotatable around the axis of the image intensifier.

The lens 9 creates an intermediate image at the point of the field lens 10, the beam transmitted by this lens

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len are inclined by an angle of less than 45 ° to the optical axis Plane mirror 11 thrown in the direction of a second lens 13, which is located in the lower part of the vertical Pipe section 12 is located. The objective 13 delivers an image in the focal plane of the eyepiece 21, the beam path is bent four times, namely by the hypotenuse surfaces of the prisms 14 and 16 and by the parallel, inclined surfaces of an ihombohedral prism 20t the prism 14 is right angled. The prism 15 is truncated and has an apex angle that is slightly smaller than 90 ° is, so that the pipe section 17 at a small angle against the image intensifier is inclined. The level through the The axes of the parts 15 and 17 are approximately perpendicular to the plane in which the axes of the parts 8 and 12 lie. It follows that the plane mirrors 7 and 11 laugh with the hypotenuse, the prisms 14 and 16 in the manner of the reflective ones Faces arranged in a Porro prism approach of the first type and provide complete image erection. For a correct understanding it should be noted that the angle between the two planes mentioned is somewhat of a right Angle may vary. This results in a certain image rotation, but this can be compensated for by the fact that the tube 17 with the prism 16 by the same angle around the Axis of the tube15 is arranged rotated. The latter Arrangement can be useful, for example, if the eyepiece is to assume a certain spatial position.

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The prism housing 19 engages around with a ring 18 the pipe section 17 and is rotatable about the axis of this pipe section. As a result, the eyepiece 21 can be pivoted in a circle be (cf. Pig, 2 »), the rhombohedral Prism 20 ensures that the image retains its spatial position. As is known, the prism 20 has no influence on the orientation of the image. The imaging elements of the whole device, namely

the image intensifier tube 2 through the lenses 4 and 9

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formed lens, the lens / and the eyepiece 21 result together an odd number of image reversals, Das However, the Porro system consisting of the first four reflective surfaces results in a complete erection of the image, without that additional elements have to be added ».

S chut zans claim

Claims (1)

• Α. 758 056 * 11/25/63 - 8 -. ■■■■ - ■■ Claim to protection Periscope-like viewing device for X-ray image intensifiers, which device besides the imaging optical elements, such as one or more lenses and an eyepiece, at least four planar, reflective Contains surfaces which bend the optical axis of the device in such a way that the exit pupil of the device closer to the patient than the screen of the image intensifier tube and the direction of view of the patient is directed to, wherein an upright image of the primary X-ray image can be observed, characterized in that the imaging elements of the image intensifier and the viewing device together produce an odd number of inversions of the primary radiograph, and the four see flat, reflective surfaces like a Porro * Prism set of the first type are arranged.