| 摘要 |
A detector for low energy x-rays employs a lithium doped silicon crystal and an FET preamplifier cooled cryogenically. In order to avoid contamination of the crystal and FET by oil vapors and other condensates produced during evacuation of an instrument for producing soft x-rays, the detector is provided with two ultra-thin windows spaced apart and defining a space which connects with the instrument. Thus, while the instrument is evacuated air is also withdrawn from the space between the windows, and when air is introduced, the air flows through a filter prior to entering that space. The air is thus filtered to remove contaminants. The windows consist of thin films of a synthetic resin which transmit low energy x-rays substantially without attentuation but because they are so thin, they are unable to withstand any substantial pressure.
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