When nearly 30 years ago Dr. Jacob Fraden invented an ear thermometer working on this second principle, the infrared light sensor was so large that he needed a narrow gold-plated reflective tube to channel the light from the ear drum to the sensor.

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But now the simple invention of a cathode ray tube, transforming light into electrons, registering their impact on the magnetic tape, had torn the curtain away.

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At one end of the tube is a source of ultraviolet light and at the other a detector.

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Then your doctor uses a thin tube equipped with a camera lens and light (laparoscope) to view the area.

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His device will reportedly stream damp air containing microscopic water particles through a tube, while a laser diode beams light through the vessel onto a sensor located on the opposite side.

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The laparoscope is a flexible controllable tube, with a camera and a bright light at the end, which allows the surgeon to see inside a patient's body.

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Unlike conventional cameras, our femto camera captures an image as one thin slice at a time of one-dimensional space using a "streak tube, " a laboratory instrument that is commonly used by chemists to study light passing through chemical samples.

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