Flat Panel X-ray Source Patent to Stellarray

Austin, TX
April 10, 2012

Stellarray, Inc., announced today that parent company Stellar Micro Devices (SMD) has been issued U.S. Patent 8,155,273 “Flat Panel X-ray Source” by the U.S. Patent and Trademark Office. This property was assigned to Stellarray when the company was spun out of SMD, along with all other SMD technology in the area of radiation sources emitting below the visible band. The inventors are Mark Eaton and Leonid Karpov, and the priority goes back to an original filing in February 2006. This patent covers a range of radiation source technologies, including the continuously emitting flat panel x-ray sources now being made at Stellarray, pixelated x-ray sources under development for imaging applications, and x-ray sources combined with UV-C emission from phosphors.

The distinguishing feature of these sources is the use of a cathode array plate and an anode plate which are opposite each other and form the major parts of the vacuum enclosure of the source. Electrons are emitted at high potential from the cathodes in the array, shoot across the vacuum gap and hit the anode to make x-rays. These then emit out the cathode array window, going through or by the cathodes. This source design has many advantages. One, which is key in the blood irradiator under development at Stellarray, is that the back side of the anode is exposed to atmosphere or some cooling medium, so that heat can be carried away. The anode is a broad, flat piece of metal, so the heat load on any portion is moderate. This means the source can be run for long portions of time. People have been trying to use x-ray tubes to irradiate or sterilize things like food since soon after the x-ray tube was invented in 1897. That has never been practical, until now, since x-ray tubes have just one spot on the anode, which is inside the tube, and all the heat generated by x-ray production can’t be efficiently carried outside the tube.

Stellarray is building an important portfolio of intellectual properties for its x-ray sources and systems using them, including proprietary knowledge of how to build them. The company hold two issued patents and one pending, originally to SMD, in the vacuum sealing area, one issued patent and three pending in x-ray systems and sources, and two pending patents in UV-C sources. For further information please contact Mark Eaton at 512/997-7781 or eaton@stellar-micro.com.