# US 2025/0149286 A1 · High dose rate radiotherapy systems and targets > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0149286 A1 - Document ID: US20250149286A1 - Status: Published application - Kind: A1 - Application number: 18/501,551 - Filed: 2023-11-03 - Published: 2025-05-08 - Earliest claimed: 2023-11-03 - Assignees: Varian Medical Systems, Inc. - Applicants: Varian Medical Systems, Inc. - Inventors: Md AHMED; Joshua MCNEUR - Web page: https://patentgrep.com/patent/US20250149286A1 ## CPC - H01J 35/147: {Spot size control} - A61N 5/1045: {using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT} - H01J 35/153: {Spot position control} - A61N 2005/1091: {Kilovoltage or orthovoltage range photons} - H01J 2235/1204: of the anode - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) ## Abstract A radiation system includes an X-ray target configured to convert an electron beam into an X-ray beam. The X-ray target includes a plurality of target layers and each of the plurality of target layers are configured to convert a portion of the electron beam into a portion of the X-ray beam. ## Claims ### Claim 1 A radiotherapy system comprising: an X-ray target configured to convert an electron beam into an X-ray beam, the X-ray target including, a plurality of target layers, each of the plurality of target layers configured to convert a portion of the electron beam into a portion of the X-ray beam. ### Claim 2 (depends on 1) The radiotherapy system of claim 1, wherein a diameter of each of the plurality of target layer corresponds to a divergence of a beam spot size. ### Claim 3 (depends on 1) The radiotherapy system of claim 1, wherein the radiotherapy system is configured to control the electron beam such that the X-ray beam delivers a radiation rate of at least 40 grays per second (Gy/s). ### Claim 4 (depends on 1) The radiotherapy system of claim 1, wherein the radiotherapy system is configured to control the electron beam such that the X-ray beam delivers a radiation rate of at least 1 gray per second (Gy/s). ### Claim 5 (depends on 1) The radiotherapy system of claim 1, wherein the plurality of target layers are stacked in series. ### Claim 6 (depends on 5) The radiotherapy system of claim 5, wherein the plurality of target layers are separated by a same distance. ### Claim 7 (depends on 5) The radiotherapy system of claim 5, wherein a first distance between a first target layer of the plurality of target layers and a second target layer of the plurality of target layers is different than a second distance between the second target layer of the plurality of target layers and a third target layer of the plurality of target layers. ### Claim 8 (depends on 1) The radiotherapy system of claim 1, wherein the plurality of target layers includes at least one of tantalum (Ta) or tungsten (W). ### Claim 9 (depends on 1) The radiotherapy system of claim 1, further comprising: a heat transfer material between at least two target layers of the X-ray target. ### Claim 10 (depends on 9) The radiotherapy system of claim 9, wherein the heat transfer material has a high thermal conductivity. ### Claim 11 (depends on 10) The radiotherapy system of claim 10, wherein the heat transfer material includes copper. ### Claim 12 (depends on 1) The radiotherapy system of claim 1, further comprising: a plurality of heat transfer material layers associated with the plurality of target layers, respectively, each heat transfer material layer and respective target layer forming a paired layer, wherein the paired layers are spaced apart along a central axis of the electron beam. ### Claim 13 (depends on 12) The radiotherapy system of claim 12, wherein the paired layers are spaced apart equidistantly. ### Claim 14 (depends on 1) The radiotherapy system of claim 1, further comprising: a plurality of heat sink layers receiving the plurality of target layers, respectively, each heat sink layer and respective target layer forming a paired layer, wherein the paired layers are spaced apart along a central axis of the electron beam. ### Claim 15 (depends on 14) The radiotherapy system of claim 14, wherein each heat sink layer includes a receiving area having a size corresponding to the respective target layer. ### Claim 16 (depends on 14) The radiotherapy system of claim 14, further comprising: at least one cooling apparatus coupled to at least one of the paired layers and configured to supply a cooling fluid. ### Claim 17 (depends on 16) The radiotherapy system of claim 16, wherein the at least one cooling apparatus is a pipe. ### Claim 18 (depends on 16) The radiotherapy system of claim 16, wherein the at least one paired layer defines a channel in the associated heat sink layer to receive the cooling fluid. ### Claim 19 (depends on 1) The radiotherapy system of claim 1, wherein the X-ray target is configured to absorb at least 90% of electrons of the electron beam, the electron beam incident on the X-ray target. ### Claim 20 (depends on 19) The radiotherapy system of claim 19, wherein the X-ray target is configured to absorb at least 99% of the electrons of the incident electron beam. ### Claim 21 (depends on 20) The radiotherapy system of claim 20, wherein a number of plurality of target layers the X-ray target is adjustable based on an energy of the electron beam.