1896, THE X-RAY GENERATING MACHINE IS EXHIBITED

Today, The Grandma has been reading about the X-ray machine, that was exhibited for the first time by H. L. Smith in 1896.

An X-ray machine is a device that uses X-rays for a variety of applications including medicine, X-ray fluorescence, electronic assembly inspection, and measurement of material thickness in manufacturing operations. 

In medical applications, X-ray machines are used by radiographers to acquire X-ray images of the internal structures of living organisms, and also in sterilization.

An X-ray generator generally contains an X-ray tube to produce the X-rays. Possibly, radioisotopes can also be used to generate X-rays.

An X-ray tube is a simple vacuum tube that contains a cathode, which directs a stream of electrons into a vacuum, and an anode, which collects the electrons and is made of tungsten to evacuate the heat generated by the collision. When the electrons collide with the target, about 1% of the resulting energy is emitted as X-rays, with the remaining 99% released as heat. Due to the high energy of the electrons that reach relativistic speeds the target is usually made of tungsten even if other material can be used particularly in XRF applications.

An X-ray generator also needs to contain a cooling system to cool the anode; many X-ray generators use water or oil recirculating systems.

In medical imaging applications, an X-ray machine has a control console that is used by a radiologic technologist to select X-ray techniques suitable for the specific exam, a power supply that creates and produces the desired kVp (peak kilovoltage), mA (milliamperes, sometimes referred to as mAs which is actually mA multiplied by the desired exposure length) for the X-ray tube, and the X-ray tube itself.

The discovery of X-rays came from experimenting with Crookes tubes, an early experimental electrical discharge tube invented by English physicist William Crookes around 1869–1875. 

In 1895, Wilhelm Röntgen discovered X-rays emanating from Crookes tubes and the many uses for X-rays were immediately apparent. One of the first X-ray photographs was made of the hand of Röntgen's wife. The image displayed both her wedding ring and bones.

On January 18, 1896 an X-ray machine was formally displayed by Henry Louis Smith. A fully functioning unit was introduced to the public at the 1904 World's Fair by Clarence Dally. The technology developed quickly: In 1909 Mónico Sánchez Moreno had produced the first portable medical device and during World War I Marie Curie led the development of X-ray machines mounted in radiological cars to provide mobile X-ray services for military field hospitals.

In the 1940s and 1950s, X-ray machines were used in stores to help sell footwear. These were known as Shoe-fitting fluoroscopes. However, as the harmful effects of X-ray radiation were properly considered, they finally fell out of use. Shoe-fitting use of the device was first banned by the state of Pennsylvania in 1957. They were more a clever marketing tool to attract customers, rather than a fitting aid. Together with Robert J. Van de Graaff, John G. Trump developed one of the first million-volt X-ray generators.

An X-ray imaging system consists of a generator control console where the operator selects desired techniques to obtain a quality readable image (kVp, mA and exposure time), an x-ray generator which controls the x-ray tube current, x-ray tube kilovoltage and x-ray emitting exposure time, an X-ray tube that converts the kilovoltage and mA into actual x-rays and an image detection system which can be either a film (analog technology) or a digital capture system and a PACS.

X-ray machines are used in health care for visualising bone structures, during surgeries (especially orthopedic) to assist surgeons in reattaching broken bones with screws or structural plates, assisting cardiologists in locating blocked arteries and guiding stent placements or performing angioplasties and for other dense tissues such as tumours. Non-medicinal applications include security and material analysis.

More information: SLAC National Accelerator Laboratory

Health care has a lot of interesting machine
-learning problems -outpatient outcomes,
or when you have x-ray images
and you want to predict things.

Jeff Dean