Apparatus and method for making x-ray films

Claim 2

Apparatus for producing enhanced X-ray images of the softer tissues of the human body comprising: a source of X-raYs positioned on one side of a subject for directing a beam of X-rays toward the subject; means positioned on the side of the subject opposite said source of X-rays for receiving the X-rays transmitted through the subject and converting the resulting invisible X-ray image into a visible X-ray image; a bone image compensating filter positioned contiguous with said image conversion means in the X-ray path between said subject and the image conversion means for substantially suppressing the image of the skeletal structure in said X-ray image, said bone image compensating filter comprising a filter having an Xray resistance which varies in a continuous manner over two dimensions in such a manner as to substantially equalize the total resistance to X-rays passing through adjacent portions of a subject and wherein the inner surface of said filter to be disposed contiguous with the subject is a smooth coating of resin for reducing the effects of surface irregularity.

Claim 3

The apparatus of claim 1 wherein said filter is provided with means for removably supporting additional filter plates of uniform X-ray resistance over the portion of the subject to be observed.

Claim 4

The apparatus of claim 1 wherein said bone image compensating filter is composed of substantially homogeneous material and wherein the thickness of said filter varies from point-to-point in a manner substantially proportional to the intensity of transmitted X-rays passing through corresponding adjacent points of the subject.

Claim 5

Apparatus for producing enhanced X-ray images of the softer tissues of the human body, comprising: a source of X-rays positioned on one side of a subject for directing a beam of X-rays toward the subject, means positioned on the side of the subject opposite said source of X-rays for receiving the X-rays transmitted through the subject and converting the resulting invisible X-ray image into a visible X-ray image: a bone image compensating filter positioned contiguous with said image conversion means in the X-ray path between said subject and the image conversion means for substantially suppressing the image of the skeletal structure in said X-ray image, said bone image compensating filter comprising a filter having an X-ray resistance which varies in a continuous manner over two dimensions in such a manner as to substantially equalize the total resistance to X-rays passing through adjacent portions of a subject; a rigid framework for holding said filter means in an operative position; and spaced support means on the framework facing the image conversion means and extending therefrom for supporting additional filter plates on said framework.

Claim 6

Apparatus for producing enhanced X-ray images of the softer tissues of the human body, comprising: a source of X-rays positioned on one side of a subject for directing a beam of X-rays toward the subject, means positioned on the side of the subject opposite said source of X-rays for receiving the X-rays transmitted through the subject and converting the resulting invisible X-ray image into a visible X-ray image: a bone image compensating filter positioned contiguous with said image conversion means in the X-ray path between said subject and the image conversion means for substantially suppressing the image of the skeletal structure in said X-ray image, said bone image compensating filter comprising a filter having an X-ray resistance which varies in a continuous manner over two dimensions in such a manner as to substantially equalize the total resistance to X-rays passing through adjacent portions of a subject; a rigid framework for holding said filter means in an operative position; and spaced support means on the framework facing the image conversion means and extending therefrom for supporting additional filter plates on said framework.

Claim 7

Apparatus as in claim 4 wherein the inner surface of said filter is coated with a smooth coating of resin for reducing the effects of surface irregularity.