JP2005332785A - Laser plasma x-ray generating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve stable formation and recovery of a cryo-target layer to be irradiated with convergent pulsed laser light and to thereby achieve stable generation of pulsed X-rays. <P>SOLUTION: A crystal fixing groove 85 in which a target material supplied from a target gas supply port 4 is to be deposited is provided at a location to be irradiated with convergent pulsed laser light in a rotary drum part 8 that moves in a rotating direction and an axial direction, so that a falling-off of the target material due to impact of the laser irradiation, for example, is prevented. On an inner surface of the cryogenic cover 5, orifices 86, 87 are formed on both sides with the crystal fixing groove 85 located in between, and sharp-pointed annular projections 89, 90 are provided to allow a space 88 between the orifices 86, 87 to serve as a gas sealing part. The space 88 is divided into a plurality of spaces with a partition 91, and the target gas supply port 4 is provided in each of the spaces to supply the target gas evenly. It is thus possible to keep the target gas in high density and to thereby recover the cryo-target layer stably. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The invention of this application generates high-temperature and high-density plasma by condensing and irradiating pulsed laser light having a high peak power and repeatedly output at a predetermined frequency, using a solid target material as a target. The present invention relates to a laser plasma X-ray generator that continuously and repeatedly generates pulse X-rays (laser plasma X-rays) from density plasma. Particularly, a target material that is chemically inert and in a gaseous state at room temperature is cooled to a cryogenic temperature by liquid nitrogen or the like. A laser that is cooled by bringing it into contact with the outer surface of the cooled rotating cylinder, solidifies into crystals, and is formed on the outer surface of the rotating cylinder as a cryotarget layer that is applied as a target for pulsed laser light irradiation. The present invention relates to a plasma X-ray generator.

  High-density plasma is generated by irradiating and condensing pulsed laser light with high peak power, which is repeatedly output at a predetermined frequency, using a solid target substance as a target. As a laser plasma X-ray generator that continuously and repeatedly generates (laser plasma X-rays), liquids of chemically inert and gaseous target materials such as Ke (xenon) developed by the present inventors. By contacting the outer surface of the rotating cylinder cooled to a cryogenic temperature with nitrogen or the like, the cryotarget layer is cooled and solidified to form crystals that adhere to the outer surface of the rotating cylinder. Conventionally known is a laser plasma X-ray generator that uses a pulse laser beam irradiation target (see Patent Documents 1 and 2).

In this laser plasma X-ray generator, the spatially fixed pulse laser beam is focused on the focused irradiation point by moving the rotating cylinder in the rotational direction or axial direction, or by combining these two directions. The surface of the rotating cylindrical body having the cryo target layer moves in the plane direction, and the focused irradiation point moves on the surface of the rotating cylindrical body. Meanwhile, the target material is continuously supplied, and the focused laser beam irradiation is performed. The cryo-target layer in which the crater hole has been generated by the plasma generation by is repaired. Then, pulsed laser light repeatedly output at a predetermined frequency is sequentially focused and irradiated on the repaired portion of the cryotarget layer surface, and pulse X-rays are continuously generated repeatedly.
JP 2001-357997 A JP 2001-357998 A

  However, in the above-mentioned conventional laser plasma X-ray generator, the target material is attached only by the fixing force due to contact with the outer surface of the rotating cylindrical body cooled to a cryogenic temperature and solidified, so that the pulse laser beam irradiation May cause peeling due to the thermal shock caused by the vertical movement of the rotating cylinder, and if it is peeled off, not only can stable pulse X-rays be generated, but also the laser beam directly hits the rotating cylinder and erodes the holes. There is a danger

  Further, in the conventional laser plasma X-ray generator, in order to prevent generated soft X-rays (pulse X-rays) from being absorbed by molecules such as xenon gas supplied as a target material, a rotating cylindrical body is used. It is necessary to cover the cover with a cover (cryo cover), and to use the vacuum chamber around the cover to suck out the leaked xenon gas etc. with a vacuum pump and keep it at a certain degree of vacuum at all times. If the vacuum chamber around the cover is used to maintain a certain degree of vacuum, the target material such as xenon gas supplied for repair of the cryo target layer leaks into the vacuum chamber more and more at the repair site. The gas density of the target material decreases, the repair speed of the cryo target layer of the laser beam irradiation trace becomes slow, Recovery is not stable, the generation of pulse X-rays may become unstable.

  The present invention solves these problems by supplying a target material such as xenon gas, which is chemically inert and in a gaseous state at room temperature, to the outer surface of a rotating cylinder cooled to a very low temperature and solidified. A laser plasma X-ray generator capable of stably forming a cryo-target layer to be formed at a position where pulse laser light on the outer surface of a rotating cylindrical body is focused and irradiated, and generating pulse X-rays stably The purpose is to provide.

  The laser plasma X-ray generator according to the first aspect of the present invention supplies a target material that is chemically inert and in a gaseous state at room temperature in a gaseous state, and introduces a refrigerant such as liquid nitrogen into the cryogenic temperature. By contacting the outer surface of the cooled rotating cylinder, it is cooled and solidified to form crystals that form a cryotarget layer attached to the outer surface of the rotating cylinder. By focusing and irradiating pulsed laser light having a peak power and repeatedly output at a predetermined frequency, spatial movement can be achieved by moving the rotating cylindrical body in the rotational direction or axial direction, or by combining these two directions. The outer surface of the rotating cylindrical body on which the cryotarget layer is formed is moved in the plane direction with respect to the focused irradiation point of the pulsed laser beam fixed to the surface of the rotating cylindrical body. The high temperature and high density plasma is generated by the focused irradiation of the pulsed laser beam, and the cryo target layer in which the crater hole is generated by the plasma conversion by the focused laser beam is applied to the target. In a laser plasma X-ray generator that repairs by supplying a material and continuously generates pulse X-rays from the high-temperature and high-density plasma, a position where the pulsed laser light on the outer surface of the rotating cylinder is focused and irradiated A crystal fixing groove for depositing a target material is provided on the substrate, and a target material supply port is arranged so that the target material is supplied toward the crystal fixing groove.

  In this laser plasma X-ray generator, a chemically inactive target material, such as Ke (xenon), which is in a gas state at room temperature, is supplied in a gas state toward the crystal fixing groove on the outer surface of the rotating cylinder. Then, the target material in the gaseous state comes into contact with the wall of the crystal fixing groove on the outer surface of the rotating cylinder cooled to a cryogenic temperature, and is cooled, solidified and attached as crystals, deposited, A target layer is formed. The surface of the cryo-target layer is focused and irradiated with pulsed laser light having a high peak power, thereby generating high-temperature high-density plasma and generating pulse X-rays from the high-temperature high-density plasma. Then, the outer surface of the rotating cylindrical body is moved with respect to the focused irradiation point of the pulse laser beam spatially fixed by the movement of the rotating cylindrical body in the rotational direction or the axial direction or the combination of the movement in the two directions. The converging irradiation point moves on the cryo target layer formed in the crystal fixing groove on the outer surface of the rotating cylindrical body while moving in the plane direction, while the target material is continuously supplied, and the pulse laser beam The cryo-target layer in which the crater hole is generated by the plasma generation by the focused irradiation is repaired.

  At that time, the wall surface of the crystal fixing groove on the outer surface of the rotating cylindrical body is close to the inner surface of the rotating cylindrical body and has good heat transfer with the refrigerant introduced into the rotating cylindrical body, so that it is easily cooled. The supplied target material condenses and adheres quickly. Therefore, the repair of the cryo target layer is accelerated, and the target material is not easily peeled off due to thermal shock caused by pulse laser light irradiation or vertical movement of the rotating cylindrical body by being held in the groove. In addition, by attaching the target material in the groove, a cryo-target layer having a large thickness can be formed and stably held at the position where the pulse laser beam is focused and irradiated.

  Thus, a cryo-target layer formed by supplying a target material such as xenon gas that is chemically inert and in a gaseous state at room temperature to solidify is formed at a position where the pulse laser beam on the outer surface of the rotating cylindrical body is focused and irradiated. It can be formed stably, can be repaired stably, and can generate pulse X-rays stably.

  A laser plasma X-ray generator according to a second aspect of the present invention includes a substantially cylindrical cover and a rotating cylindrical body that rotates inside the cover, and is chemically inert from a target material supply port provided in the cover. The target material in the gaseous state at room temperature is supplied in the gaseous state, and the refrigerant is introduced into the interior and brought into contact with the outer surface of the rotating cylinder cooled to a cryogenic temperature, thereby cooling and solidifying into crystals. Forming a cryotarget layer attached to the outer surface of the rotating cylindrical body, condensing and irradiating the surface of the cryotarget layer with pulsed laser light having a high peak power and repeatedly output at a predetermined frequency, By moving the rotating cylinder in the rotational direction or axial direction, or a combination of these two movements, a cryogenic beam is focused on the focused and irradiated point of the pulse laser beam. The outer surface of the rotating cylinder having the target layer is moved in the plane direction, the focused irradiation point is relatively moved on the outer surface of the rotating cylinder, and the high-temperature and high-density plasma is generated by the focused irradiation of the pulse laser beam. The cryotarget layer in which the crater hole is generated by the plasma generation by the focused irradiation of the pulsed laser beam is repaired by supplying the target material supplied from the target material supply port, and the pulse is generated from the high-temperature high-density plasma. In the laser plasma X-ray generator for continuously generating X-rays, a crystal fixing groove for depositing a target material is provided on the outer surface of the rotating cylindrical body at a position where the pulsed laser beam is focused and irradiated. The target material supply port is arranged so that the target material is supplied toward the fixed groove, and the inner surface of the cover An orifice is formed around the outer surface of the rotating cylindrical body at a position beyond both ends of the crystal fixing groove on the outer surface of the rotating cylindrical body on both sides in the axial direction across the target material supply port. A pointed annular projection is provided to make the space defined on both sides in the axial direction substantially sealed.

  In this laser plasma X-ray generator, from a target material supply port provided in a cover around a rotating cylindrical body, a target material that is chemically inert at room temperature, such as Ke (xenon), is in a gas state. It is supplied toward the crystal fixing groove on the outer surface of the rotating cylinder. Then, the target material in the gas state is held at a high pressure by being substantially confined in a substantially sealed space defined on both sides in the axial direction by the orifice formed by the pointed annular projection on the inner surface of the cover, The target material in a gaseous state with high pressure and high density comes into contact with the wall of the crystal fixing groove on the outer surface of the rotating cylinder cooled to a very low temperature, and is cooled, solidified, attached as crystals, and deposited. Thus, a cryotarget layer is formed in the crystal fixing groove. The surface of the cryo-target layer is focused and irradiated with pulsed laser light having a high peak power, thereby generating high-temperature high-density plasma and generating pulse X-rays from the high-temperature high-density plasma. Then, the outer surface of the rotating cylindrical body is moved with respect to the focused irradiation point of the pulse laser beam spatially fixed by the movement of the rotating cylindrical body in the rotational direction or the axial direction or the combination of the movement in the two directions. The converging irradiation point moves on the cryo target layer formed in the crystal fixing groove on the outer surface of the rotating cylindrical body while moving in the plane direction, while the target material is continuously supplied, and the pulse laser beam The cryo-target layer in which the crater hole is generated by the plasma generation by the focused irradiation is repaired.

  At that time, the wall surface of the crystal fixing groove on the outer surface of the rotating cylindrical body is close to the inner surface of the rotating cylindrical body and has good heat transfer with the refrigerant introduced into the rotating cylindrical body, so that it is easily cooled. In addition, since the target material supplied in a gas state is maintained at a high pressure in a substantially sealed space partitioned by orifices, the target material quickly solidifies and adheres as crystals. Therefore, the repair of the cryo-target layer is accelerated, and the target material is not easily peeled off due to the thermal shock caused by the pulse laser beam irradiation or the vertical movement of the rotating cylindrical body by being held in the groove. In particular, the pointed annular protrusion forming the orifice scrapes off the target material adhering to the surface of the cylindrical rotating body that is not the crystal fixing groove, but the target material held in the crystal fixing groove is difficult to drop off. In addition, by attaching the target material in the groove, a cryo-target layer having a large thickness can be formed and stably held at the position where the pulse laser beam is focused and irradiated.

  Thus, a cryo-target layer formed by supplying a target material such as xenon gas that is chemically inert and in a gaseous state at room temperature to solidify is formed at a position where the pulse laser beam on the outer surface of the rotating cylindrical body is focused and irradiated. It can be formed stably, can be repaired stably, and can generate pulse X-rays stably.

  According to a third aspect of the present invention, there is provided a laser plasma X-ray generator comprising: a substantially cylindrical cover disposed in a vacuum chamber; and a rotating cylindrical body that rotates inside the cover; The target material in a gaseous state at room temperature that is chemically inert from the mouth is supplied in a gaseous state, and cooled by introducing a refrigerant into the interior and bringing it into contact with the outer surface of a rotating cylinder cooled to a cryogenic temperature. A pulsed laser beam which is solidified to form crystals and forms a cryotarget layer adhering to the outer surface of the rotating cylindrical body, and has a high peak power and is repeatedly output at a predetermined frequency on the surface of the cryotarget layer And a laser beam spatially fixed by a combination of movement in the rotational direction or axial direction of the rotating cylindrical body or movement in the two directions. The outer surface of the rotating cylindrical body having the cryotarget layer is moved in the plane direction with respect to the focused irradiation point, the focused irradiation point is moved relative to the outer surface of the rotating cylindrical body, and the pulse laser beam A high-temperature and high-density plasma is generated by focused irradiation, and a cryotarget layer in which a crater hole is generated due to plasma formation by focused irradiation of the pulsed laser light is repaired by supplying the target material supplied from the target material supply port. In the laser plasma X-ray generator for continuously generating pulse X-rays from the high-temperature high-density plasma, a target material is deposited on the outer surface of the rotating cylindrical body at a position where the pulsed laser light is focused and irradiated. When a crystal fixing groove is provided and the target material supply port is arranged so that the target material is supplied toward the crystal fixing groove In addition, the outer surface of the rotating cylindrical body is located on both sides in the axial direction across the target material supply port on the inner surface of the cover, at positions exceeding the axial ends of the crystal fixing grooves on the outer surface of the rotating cylindrical body. An orifice is formed around the tip, and a pointed annular projection is provided in which the space defined by the orifices on both sides in the axial direction is substantially sealed.

  In this laser plasma X-ray generator, from a target material supply port provided in a cover around a rotating cylindrical body, a target material that is chemically inert at room temperature, such as Ke (xenon), is in a gas state. It is supplied toward the crystal fixing groove on the outer surface of the rotating cylinder. The supplied target material leaks into the vacuum chamber due to the pressure difference, but the pointed annular protrusion on the inner surface of the cover forms an orifice, and the conductance with respect to the vacuum chamber, which is partitioned on both sides in the axial direction by the orifice, is small. By supplying the target material in the gas state to the substantially sealed space, the resistance to leakage is large and the pressure is kept high. Then, the target material in a gas state with a high pressure and a high density comes into contact with the wall of the crystal fixing groove on the outer surface of the rotating cylinder cooled to a cryogenic temperature, and is cooled, solidified and attached as crystals. Then, a cryo target layer is formed in the crystal fixing groove. The surface of the cryo-target layer is focused and irradiated with pulsed laser light having a high peak power, thereby generating high-temperature high-density plasma and generating pulse X-rays from the high-temperature high-density plasma. Then, the outer surface of the rotating cylindrical body is moved with respect to the focused irradiation point of the pulse laser beam spatially fixed by the movement of the rotating cylindrical body in the rotational direction or the axial direction or the combination of the movement in the two directions. The converging irradiation point moves on the cryo target layer formed in the crystal fixing groove on the outer surface of the rotating cylindrical body while moving in the plane direction, while the target material is continuously supplied, and the pulse laser beam The cryo-target layer in which the crater hole is generated by the plasma generation by the focused irradiation is repaired.

  At that time, the wall surface of the crystal fixing groove on the outer surface of the rotating cylindrical body is close to the inner surface of the rotating cylindrical body and has good heat transfer with the refrigerant introduced into the rotating cylindrical body, so that it is easily cooled. In addition, the substantially sealed space defined by the orifice has a large pressure difference but a small conductance with respect to the vacuum chamber. Therefore, the target material supplied in the gas state is maintained at a high pressure at the repaired portion of the cryo target layer and cooled. It quickly solidifies and attaches as crystals. Therefore, the cryo target layer is repaired quickly and is held in the groove, so that the target material is not easily peeled off due to thermal shock caused by pulse laser light irradiation or vertical movement of the rotating cylinder, and in particular, an orifice is formed. The pointed annular protrusion scrapes off the target material adhering to the surface of the cylindrical rotating body that is not the crystal fixing groove, but the target material held in the crystal fixing groove is difficult to drop off. In addition, by attaching the target material in the groove, a cryo-target layer having a large thickness can be formed and stably held at the position where the pulse laser beam is focused and irradiated.

  Thus, a cryo-target layer formed by supplying a target material such as xenon gas that is chemically inert and in a gaseous state at room temperature to solidify is formed at a position where the pulse laser beam on the outer surface of the rotating cylindrical body is focused and irradiated. It can be formed stably, can be repaired stably, and can generate pulse X-rays stably.

  According to a fourth aspect of the present invention, there is provided a laser plasma X-ray generator comprising a substantially cylindrical cover disposed in a vacuum chamber and a rotating cylindrical body rotating inside the cover, and a target material supply provided on the cover The target material in a gaseous state at room temperature that is chemically inert from the mouth is supplied in a gaseous state, and cooled by introducing a refrigerant into the interior and bringing it into contact with the outer surface of a rotating cylinder cooled to a cryogenic temperature. A pulsed laser beam which is solidified to form crystals and forms a cryotarget layer adhering to the outer surface of the rotating cylindrical body, and has a high peak power and is repeatedly output at a predetermined frequency on the surface of the cryotarget layer And a laser beam spatially fixed by a combination of movement in the rotational direction or axial direction of the rotating cylindrical body or movement in the two directions. The outer surface of the rotating cylindrical body having the cryotarget layer is moved in the plane direction with respect to the focused irradiation point, the focused irradiation point is moved relative to the outer surface of the rotating cylindrical body, and the pulse laser beam A high-temperature and high-density plasma is generated by focused irradiation, and a cryotarget layer in which a crater hole is generated due to plasma formation by focused irradiation of the pulsed laser light is repaired by supplying the target material supplied from the target material supply port. In a laser plasma X-ray generator that continuously generates pulse X-rays from the high-temperature high-density plasma, a target material is deposited on the outer surface of the rotating cylindrical body at a position where the pulsed laser light is focused and irradiated. A crystal fixing groove is provided, and the target material supply port is arranged so that the target material is supplied toward the crystal fixing groove. Both of the outer surfaces of the rotating cylinders are positioned on both sides in the axial direction across the target material supply port on the inner surface of the cover at positions beyond the axial ends of the crystal fixing grooves on the outer surface of the rotating cylinder. A pointed annular projection is provided in which an orifice is formed around and a space defined on both sides in the axial direction by the orifice is substantially sealed, and a plurality of spaces defined on the both sides in the axial direction are provided in the circumferential direction by the orifice. A plurality of partition portions that are divided into spaces and are each substantially sealed are provided, and the target material supply ports are respectively arranged in the plurality of spaces.

  In this laser plasma X-ray generator, a pointed annular projection on the inner surface of the cover forms an orifice, and both sides in the axial direction are partitioned by the orifice. The space is divided into a plurality of spaces in the circumferential direction by the respective portions, each being substantially sealed, and a target material supply port is disposed in the cover around the rotating cylindrical body with respect to the plurality of spaces. A target material that is chemically inert and in a gaseous state at room temperature, such as Ke (xenon), is supplied in a gaseous state toward the crystal fixing groove on the outer surface of the rotating cylinder. The supplied target material leaks into the vacuum chamber due to a pressure difference, but the gas-state target material is evenly distributed in a plurality of substantially sealed spaces each having a small conductance with respect to the vacuum chamber and a large resistance to leakage. By being supplied, each space is maintained at a substantially high pressure. Then, the target material in a gas state with a high pressure and a high density comes into contact with the wall of the crystal fixing groove on the outer surface of the rotating cylinder cooled to a cryogenic temperature, and is cooled, solidified and attached as crystals. Then, a cryo target layer is formed in the crystal fixing groove. The surface of the cryo-target layer is focused and irradiated with pulsed laser light having a high peak power, thereby generating high-temperature high-density plasma and generating pulse X-rays from the high-temperature high-density plasma. Then, the outer surface of the rotating cylindrical body is moved with respect to the focused irradiation point of the pulse laser beam spatially fixed by the movement of the rotating cylindrical body in the rotational direction or the axial direction or the combination of the movement in the two directions. The converging irradiation point moves on the cryo target layer formed in the crystal fixing groove on the outer surface of the rotating cylindrical body while moving in the plane direction, while the target material is continuously supplied, and the pulse laser beam The cryo-target layer in which the crater hole is generated by the plasma generation by the focused irradiation is repaired.

  At that time, the wall surface of the crystal fixing groove on the outer surface of the rotating cylindrical body is close to the inner surface of the rotating cylindrical body and has good heat transfer with the refrigerant introduced into the rotating cylindrical body, so that it is easily cooled. In addition, the substantially sealed space divided in the axial direction by the orifice and further divided in the circumferential direction by the partition portion has a large pressure difference but a small conductance with respect to the vacuum chamber. The target material supplied in the gas state to each of the plurality of spaces is maintained at a substantially equal high pressure at the repaired portion of the cryo target layer in each of the plurality of spaces, and is quickly cooled and cooled. Solidifies and attaches as crystals. Therefore, the cryo target layer is repaired quickly and is held in the groove, so that the target material is not easily peeled off due to thermal shock caused by pulse laser light irradiation or vertical movement of the rotating cylinder, and in particular, an orifice is formed. The pointed annular protrusion scrapes off the target material adhering to the surface of the rotating cylindrical body that is not the crystal fixing groove, but the target material held in the crystal fixing groove is difficult to drop off. In addition, the target material attached to the surface of the rotating cylinder is scraped by the pointed cylinder when moving in the axial direction of the rotating cylinder, and by the partition portion when moving in the rotating direction of the rotating cylinder, The adhesion of the target material becomes uniform over the entire circumference of the rotating cylinder, and the load when moving the rotating cylinder is reduced. In addition, by attaching the target material in the groove, a cryo-target layer having a large thickness can be formed and stably held at the position where the pulse laser beam is focused and irradiated.

  Thus, a cryo-target layer formed by supplying a target material such as xenon gas that is chemically inert and in a gaseous state at room temperature to solidify is formed at a position where the pulse laser beam on the outer surface of the rotating cylindrical body is focused and irradiated. It can be formed stably, can be repaired stably, and can generate pulse X-rays stably.

  As is apparent from the above description, the laser plasma X-ray generator of the present invention is a cryo-target layer formed by supplying and solidifying a target material such as xenon gas that is chemically inert and in a gaseous state at room temperature. Can be stably formed at the position where the pulse laser beam on the outer surface of the rotating cylindrical body is focused and irradiated, can be stably repaired, and pulse X-rays can be generated stably.

  1 to 4 show an example of an embodiment of the present invention. FIG. 1 is a schematic diagram showing the overall schematic configuration of the laser plasma X-ray generator of this embodiment, FIG. 2 is a detailed configuration diagram of the main part thereof, FIG. 3 is a sectional view taken along line XX, and FIG. is there.

  As schematically shown in FIG. 1, the laser plasma X-ray generator of this embodiment has a chemically inert and gaseous target material (hereinafter referred to as a target gas) inside a vacuum chamber 1. ), A cryogenic cover 5 (cover) provided with a target gas supply pipe 2 for transporting, a condensing irradiation port 3 for pulsed laser light, and a target gas supply port 4 (target material supply port), and a target gas supply The pipe 2 is connected so as to introduce the target gas into the cryogenic cover 5 (FIG. 1 shows a schematic configuration and is actually connected via a target gas distributor as will be described later). A rotating cylindrical body 6 is installed inside the conversion cover 5 so as to be movable in the rotational direction and the axial direction. The illustrated example is a vertical type device in which the rotating cylindrical body 6 is arranged in the vertical direction with respect to the vacuum chamber 1, but a horizontal type device in which the rotating cylindrical body 6 is tilted sideways with a similar structure may be used. .

  The rotating cylindrical body 6 has a hollow inside, and is composed of a rotating shaft portion 7 for driving in the rotating direction and the axial direction, and a rotating drum portion 8 for forming a cryotarget layer. A refrigerant introduction pipe 9 is inserted into the rotating cylindrical body 6 so as to pass through the rotating shaft portion 7 and reach the inside of the rotating drum portion 8.

  The rotating shaft portion 7 extends through the wall portion of the vacuum chamber 1 to the outside. And the vacuum seal part 10, such as an O-ring and a magnetic fluid, is provided in the penetration part.

  Since the rotating shaft portion 7 of the rotating cylindrical body 6 is in contact with the vacuum seal portion 10, it is made of a material having poor heat conduction. Further, the rotating drum portion 8 is made of a material having good heat conductivity in order to cool the inside with a refrigerant such as liquid nitrogen or helium gas to keep the outer surface at a very low temperature.

  In addition, as a driving device for moving the rotating cylindrical body 6 in the rotational direction or the axial direction, or as a driving device for performing a driving combined with movement in the rotational direction and the axial direction, the rotational direction driving device 11 and the axial direction driving device. 12 are installed and connected to the rotating shaft portion 7 respectively.

  A pulse laser beam generator 13 for generating a pulse laser beam having a predetermined frequency and a high peak power is installed on the side of the vacuum chamber 1. The pulsed laser beam 16 output from the pulsed laser beam generator 13 is incident from an incident port 15 provided on the side wall of the vacuum chamber 1 through the laser condenser lens 14, and is positioned near the outer surface of the rotating drum unit 8. The light is condensed at a spatially fixed condensing irradiation point 17.

  The condensing irradiation port 3 for the pulse laser beam is formed with a hole having a minimum size required for condensing the pulse laser beam 16 and emitting X-rays generated thereby.

  The rotating cylindrical body 6 is supported by a single or a plurality of bearings 19 and 20 on the rotating shaft portion 7 side and the tip end side (lower end in the illustrated example) with the rotating drum portion 8 interposed therebetween. These bearings 19 and 20 are thrust bearings, radial bearings, a combination of thrust and radial bearings, or a bearing having the same performance as a combination of thrust and radial bearings.

  This laser plasma X-ray generator includes an optical image detector 21 that detects a crater generated on the surface of a cryotarget layer, which will be described later, by plasma formation by focused irradiation of pulsed laser light 16, and a crater based on the detection signal. By comparing the position coordinates with the position coordinates of the focused irradiation point 17 of the pulse laser beam 16, the rotation direction so that the focused irradiation point 17 of the pulsed laser beam 16 draws a predetermined locus on the outer surface of the rotating drum unit 8. A position control device 22 for controlling the driving device 11 and the axial driving device 12 to control the moving position of the rotating cylindrical body 6 is provided, and the focused irradiation of the pulse laser beam 16 is synchronized with the moving of the rotating cylindrical body 6. A synchronization control device 23 is provided.

  The vacuum chamber 1 is connected to a vacuum device 24 such as a vacuum pump, and the cryogenic cover 5 is connected to a target gas supply device 25 that supplies a pressurized target gas via a target gas supply pipe 2. .

  The pulse X-rays generated by the plasma generation by the focused irradiation of the pulsed laser beam 16 are collected and reflected by a pulse X-ray focusing mirror (not shown), and from the X-ray exit (not shown) to the vacuum chamber 1. Take out to the outside.

  The main configuration of this laser plasma X-ray generator is, for example, as shown in FIG. 2 in detail. A flange body 32 is bolted from above to a horizontal frame 31 having an open central portion. Further, from below, the bottomed cylindrical cryogenic cover 5 is arranged in a vertical state by being bolted to a connecting sleeve 35 in which flange-like connecting portions 33 and 34 are integrally welded to both upper and lower ends. The connection sleeve 35 is provided with a communication hole that communicates with the vacuum chamber 1. As a result, the inside of the cryogenic cover 5 is kept at substantially the same degree of vacuum as in the vacuum chamber 1. A bearing holder 39 is bolted to the bottom bottom of the cryogenic cover 5 from below, and the bearing 20 is held by the bearing holder 39.

  In addition, a substantially cylindrical vacuum cover 41 is disposed in a vertical state on the upper surface of the flange body 32, and is bolted through a flange-like connecting portion 42 that is integrally welded, and is surrounded by the vacuum cover 41. Thus, a substantially cylindrical bearing assembly holder 43 having a diameter smaller than that of the vacuum cover 41 is also arranged in a vertical state and fixed with bolts.

  The bearing 19 is held inside the bearing assembly holder 43 in two upper and lower stages, and a magnetic seal 46 is disposed between the upper and lower bearings 19.

  The vacuum cover 41 has a structure in which a sealed space is formed around and above the bearing assembly holder 43, and the sealed space can be held in a vacuum by a vacuum pump (not shown), and above the bearing assembly holder 43. A ring-shaped partition wall 47 is integrally welded so as to project inward, and a seal holder 50 holding seals 48 and 49 in two upper and lower stages is disposed from above and fixed to the ring-shaped partition wall 47 with bolts.

  A drive mechanism including the rotation direction drive device 11 and the axial direction drive device 12 shown in FIG. 1 is installed above the vacuum cover 41. The rotary shaft portion 7 driven in the vertical direction and the rotational direction by the drive mechanism is disposed vertically through the inside of the vacuum cover 41, and a connecting portion 51 is connected to a lower end extending portion of the rotary shaft portion 7. The rotary drum portion 8 is connected to the lower shaft portion 52, and the lower shaft portion 52 projecting downward is connected to the center of the bottom portion of the rotary drum portion 8, and the lower shaft portion 52 is held by the bearing holder 39. It is supported by. These rotating shaft 7, connecting portion 51, rotating drum portion 8 and lower shaft portion 52 constitute a rotating cylindrical body 6.

  On the other hand, a guide sleeve 53 that rotates integrally with the inner rail of the bearing 19 held inside the bearing assembly holder 43 is mounted on the outer periphery of the rotating shaft portion 7, and below this guide sleeve 53, A flange-like projection 54 that is relatively movable in the axial direction is provided on the upper outer periphery of the rotary drum portion 8, and the rotary shaft is interposed between the lower surface of the guide sleeve 53 and the upper surface of the flange-like projection 54. A bellows 55 is disposed so as to surround the portion 7, and a bearing 56 is mounted on the upper inner peripheral side of the guide sleeve 53 so as to surround the rotating shaft portion 7.

  A refrigerant introduction pipe 9 for introducing liquid nitrogen as a refrigerant is inserted inside the rotary shaft portion 7. The refrigerant introduction pipe 9 is for introducing liquid nitrogen supplied from a refrigerant supply port (not shown) at the upper part of the apparatus into the rotary drum portion 8. The outer diameter is smaller than the inner diameter of the rotary shaft portion 7, It arrange | positions so that the clearance gap S may be made. Further, a liquid level gauge 57 is inserted inside the refrigerant introduction pipe 9.

  A gap S between the rotary shaft portion 7 and the refrigerant introduction pipe 9 is sealed by a seal 58 above the seal holder 50.

  In the seal holder 50, an annular groove 59 is formed in an inner peripheral portion sandwiched between upper and lower two-stage seals 48 and 49. Further, the rotary shaft portion 7 is formed with a lateral hole 60 for opening a gap S around the refrigerant introduction pipe 9 in an annular groove 59 on the inner periphery of the seal holder 50. Then, a communication hole 61 is formed in the seal holder 50 so as to communicate with the annular groove 59 on the inner periphery of the seal holder 50 and extend laterally, and an extraction hole 62 communicating with the communication hole 61 is formed in the partition wall 47. A pipe insertion port 63 that opens to the extraction hole 62 of the partition wall 47 is formed in the vacuum cover 41.

  The cryogenic cover 5 is provided with an irradiation flange 64 for forming the condensing irradiation port 3 at a predetermined position on the outer surface of the rotating drum portion 8, and in a circumferential direction with respect to the condensing irradiation port 3 formed by the irradiation flange 64. The target gas supply ports 4 are formed at a plurality of locations (in this example, seven locations as shown in FIG. 3), and a pipe connection portion 65 communicating with each target gas supply port 4 is formed. The number of locations where the target gas supply port 4 is formed can be changed as appropriate.

  In addition, an axial connection hole 72 having an opening at a substantially lower center and a pipe connection portion 71 at the tip, and a radial direction from the connection hole 72 are provided at the lower portion of the bearing holder 39 fixed to the lower bottom surface of the cryogenic cover 5. A target gas distribution section is formed which includes a plurality of (seven in this example) distribution holes 74 that extend radially and open to the peripheral surface of the bearing holder 39 and are each provided with a pipe connection section 73 at the tip. The number of distribution holes 74 can be changed as appropriate according to the number of target gas supply ports 4.

  The target gas supply pipe 2 is connected to the pipe connection part 71 of the connection hole 72 of the target gas distribution part via a connection fitting 75a, and the target gas is connected to the pipe connection part 73 of each distribution hole 74 via the connection fitting 75b. One ends of the distribution pipes 76 are connected, and the other ends of the target gas distribution pipes 76 are connected to the pipe connection portions 65 of the target gas supply ports 4 of the cryogenic cover 5 via connection fittings 77.

  The target gas supply pipe 2 passes through a three-pronged nipple 78 fixed to the frame 31 and a three-pronged nipple 79 disposed above the target gas supply pipe 2, and extends upward from the frame 31. 81, and a pipe 82 is attached between the upper and lower nipples 78 and 79 so as to form a sealed space around the target gas supply pipe 2.

  The target gas supply pipe 2 and the pipe 82 between the upper and lower nipples 78 and 79 constitute a gas cooling heat exchanger. The upper nipple 79 has a vacuum cover 41 that opens in the outlet hole 62 of the partition wall 47. A pipe 83 for taking out the vapor gas generated in the rotary drum unit 8 and guiding it between the target gas supply pipe 2 and the pipe 82 between the upper and lower nipples 78 and 79 is connected between the pipe insertion port 63. ing. Further, a pipe 84 is connected to the lower nipple 78 in order to discharge the vapor gas flowing between the target gas supply pipe 2 and the pipe 82 into the atmosphere.

  For example, the rotating cylindrical body 6 rises 1 mm in the axial direction while making one rotation per second and rises by three rotations. When the rotation cylindrical body 6 turns up, the next three rotations go down by 1 mm every rotation while making one rotation every second. When it descends, it starts to rise again, and is controlled so as to move up and down while repeating (however, the movement pattern of the rotating cylindrical body 6 can be moved in the rotational direction or axial direction or in these two directions). It can be any pattern with a combination of movements.) As a result, the outer surface of the rotating drum portion 8 of the rotating cylindrical body 6 moves in the surface direction with respect to the condensing irradiation point 17 spatially fixed. The moving range is, for example, as described above, when the rotating cylinder 6 moves up and down by 1 mm at one rotation per second as described above, it is the entire circumference in the rotation direction and 3 mm in the vertical direction (axial direction). For example, the diameter of the crater hole generated by the above is about 0.6 mm, so that, for example, a little less than 5 mm in the vertical direction is a range in which the cryotarget is converted into plasma by the focused irradiation of the pulse laser beam.

  As shown in FIG. 4, on the outer surface of the rotary drum unit 8, the pulse laser beam is condensed at a position where the target gas is supplied from the target gas supply port 4, that is, a position where the pulse laser beam is condensed and irradiated. A crystal fixing groove 85 for depositing the target material supplied from the target gas supply port 4 is provided over a range of, for example, a little less than 5 mm along the entire rotation direction in which the cryotarget is turned into plasma by irradiation. The depth of the crystal fixing groove 85 is about 0.5 mm, for example.

  Then, the cryogenic cover 5 is rotated on the inner surface of the cryogenic cover 5 at a position beyond both ends in the axial direction of the crystal fixing grooves 85 on the outer surface of the rotating drum 8 on both sides (upper and lower) in the axial direction across the target gas supply port 4. A pointed annular projection 89 is formed so that orifices 86 and 87 are formed around the outer surface of the drum portion 8, and a space 88 defined on both sides in the axial direction by the upper and lower orifices 86 and 87 constitutes a gas-sealed portion in a substantially sealed state. , 90 are provided. When the vertical width of the crystal fixing groove 85 is less than about 5 mm, the distance between the orifices 86 and 87 is preferably about 7 mm, for example.

  Further, as shown in FIG. 3, the space 88 constituting the gas sealing portion is located with the irradiation flange 64 interposed therebetween, and a plurality of (this example) provided at predetermined intervals between the upper and lower peak annular projections 89 and 90. In this example, the number of the partition portions 91 is divided into a plurality (seven in this example) of substantially sealed spaces 88a to 88g, and each of the plurality of spaces 88a to 88g constitutes a gas sealing portion. And the target gas supply port 4 is arrange | positioned with respect to these some space 88a-88g, respectively.

  In this laser plasma X-ray generator, liquid nitrogen as a refrigerant is introduced into the inside of the rotating drum portion 8 by the refrigerant introducing pipe 9, the rotating drum portion 8 is cooled, and its outer surface is kept at a very low temperature. Then, a target material (a rare gas such as krypton, xenon, or argon) that is chemically inert and in a gas state at room temperature is supplied as a target gas through the target gas supply pipe 2 in the gas state, and the target gas is supplied as a target gas. The gas is distributed to the distribution holes 74 from the connection holes 72 of the distribution unit, and sent to the target gas supply ports 4 of the cryogenic cover 5 through the target gas distribution pipes 76. It ejects to each space 88a-88g to comprise. Then, the jetted target gas comes into contact with the wall surface of the crystal fixing groove 85 of the rotary drum portion 8, is cooled, solidifies and adheres as a crystal, deposits, and deposits in the crystal fixing groove 85. Form.

  Then, the pulse laser beam generator 13 causes the pulse laser beam having high peak power and repeatedly output at a predetermined frequency to enter through the condensing irradiation port 3 of the irradiation flange 64, and the outer surface of the rotating drum unit 8. At the spatially fixed focusing irradiation point 17 located in the vicinity, the surface of the cryotarget layer 92 in the crystal fixing groove 85 is focused and irradiated, and by the focused irradiation of the pulsed laser light, high-temperature and high-density plasma is generated. Generated and pulse X-rays are generated from the high-temperature and high-density plasma. Further, the rotary drum unit 8 moves in the rotation direction and the axial direction integrally with the rotary shaft unit 7, and thereby the spatially fixed pulse laser beam condensing irradiation point 17 of the rotary drum unit 8. The outer surface moves in the plane direction, and the focused irradiation point 17 of the pulsed laser light moves along a predetermined locus on the surface of the cryo target layer 92 in the crystal fixing groove 85, while the target gas is continuously supplied. Then, the cryotarget layer 92 (see FIG. 4) in which the crater hole 93 is generated by the plasma generation by the focused irradiation of the pulsed laser beam is repaired, and the focused irradiation of the pulsed laser beam that is repeatedly output at a predetermined frequency, Pulsed X-rays are generated continuously and repeatedly.

  In the laser plasma X-ray generator of this embodiment, the wall surface of the crystal fixing groove 85 on the outer surface of the rotating drum unit 8 is close to the inner surface of the rotating drum unit 8 and is introduced into the rotating drum unit 8. The heat transfer between and is easy to cool.

  In addition, the crystal fixing groove 85 is surrounded by a gas sealing portion constituted by a plurality of spaces 88a to 88g divided in the axial direction by the orifices 86 and 87 and divided in the circumferential direction by the partition portion 91, and these gas sealing portions. Since the pressurized target gas is supplied to each of the spaces 88a to 88g, the pressure difference from the inside of the vacuum chamber 1 is increased, but the conductance with respect to the vacuum chamber 1 is divided by the orifices 86 and 87 in the axial direction. Is small. Moreover, the target gas is uniformly supplied from the respective target gas supply ports 4 for each of the spaces 88a to 88g. Therefore, the spaces 88 a to 88 g are held at a pressure (for example, 100 to 1000 Pa) suitable for repairing the cryo target layer 92.

  Further, vapor gas of liquid nitrogen is generated inside the rotating drum unit 8, and the vapor gas rises in the gap S between the rotating shaft unit 7 and the refrigerant introduction pipe 9, and the pipe 83 of the gas cooling heat exchanger is connected by the pipe 83. 82. The target gas flowing in the target gas supply pipe 2 is cooled in this portion by heat exchange with the vapor gas, becomes a gas with low molecular energy at a low temperature with good adhesion efficiency, and each space 88a constituting the gas sealing portion. Spout to ~ 88g.

  Therefore, the target gas is quickly solidified and attached as crystals, and the cryotarget layer 92 is quickly repaired. Moreover, since the crystallized target material is held in the crystal fixing groove 85, it is difficult to peel off.

  Part of the target gas supplied to the gas sealing part leaks from the orifices 86 and 87 and crystallizes and adheres to the surface of the rotary drum 8 that is not the crystal fixing groove 85. The target material adhering to the surface of the rotating drum portion 8 is scraped off by the pointed annular projections 89 and 90 as the rotating cylindrical body 6 moves, and the target material adheres evenly over the entire circumference of the rotating drum portion 8. . Therefore, the load when moving the rotating cylinder is reduced. The target material deposited in the crystal fixing groove 85 is unlikely to drop off, and the cryo-target layer 92 having a large thickness is stably held at the position where the pulse laser beam is focused and irradiated, and is stably repaired.

  As mentioned above, although an example of the embodiment and the modified example have been described, the present invention is not limited thereto, and it is needless to say that the configuration can be appropriately changed and implemented within the scope of the technical idea of the invention.

It is a schematic diagram which shows the whole schematic structure of the laser plasma X-ray generator of embodiment of this invention. It is a principal part detailed block diagram of the laser plasma X-ray generator of embodiment of this invention. It is XX sectional drawing of FIG. It is the A section enlarged view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum chamber 2 Target gas supply pipe 3 Condensing irradiation port 4 Target gas supply port 5 Cryogenic cover 6 Rotating cylindrical body 7 Rotating shaft part 8 Rotating drum part
9 Refrigerant introduction pipe 11 Rotational direction drive device 12 Axial direction drive device 13 Pulse laser light generation device 15 Entrance 16 Pulse laser light 17 Condensing irradiation point 22 Position control device 23 Synchronization control device 24 Vacuum device 25 Target gas supply device S Gap 64 Irradiation flange 74 Distribution hole 76 Target gas distribution pipe 85 Crystal fixing groove 86, 87 Orifice 88 (88a-88g) Space 89, 90 Pointed annular projection 91 Partition part constituting gas sealing part

Claims (4)

A target material that is chemically inert and in a gaseous state at room temperature is supplied in a gaseous state, and is cooled by bringing it into contact with the outer surface of a rotating cylinder cooled to a cryogenic temperature by introducing a refrigerant therein. A cryotarget layer is formed as a crystal and adhered to the outer surface of the rotating cylindrical body, and pulse laser light having high peak power and repeatedly output at a predetermined frequency is collected on the surface of the cryotarget layer. The cryo-target layer is applied to a focused irradiation point of pulse laser light spatially fixed by irradiating with light and moving in the rotational direction or axial direction of the rotating cylinder or a combination of movement in the two directions. By moving the outer surface of the rotating cylindrical body formed with a plane in the plane direction, relatively moving the focused irradiation point on the outer surface of the rotating cylindrical body, and performing the focused irradiation of the pulse laser beam. A high temperature and high density plasma is generated, and a cryo target layer in which a crater hole is generated by plasma formation by the focused irradiation of the pulsed laser light is repaired by supplying the target material, and pulse X-rays are continuously generated from the high temperature and high density plasma. In a laser plasma X-ray generator that repeatedly generates
A crystal fixing groove for depositing the target material is provided on the outer surface of the rotating cylindrical body where the pulse laser beam is condensed and irradiated, and a target material supply port is provided so that the target material is supplied toward the crystal fixing groove. A laser plasma X-ray generator characterized by being arranged. A substantially cylindrical cover and a rotating cylindrical body that rotates inside the cover are provided, and a target material that is chemically inert and gaseous at room temperature is supplied in a gas state from a target material supply port provided in the cover. Then, by introducing a refrigerant into the inside and bringing it into contact with the outer surface of the rotating cylinder cooled to a cryogenic temperature, it cools and solidifies into a crystal to form a cryo target layer attached to the outer surface of the rotating cylinder. Then, the surface of the cryotarget layer is focused and irradiated with pulsed laser light having a high peak power and repeatedly output at a predetermined frequency, and the rotational cylinder is moved in the rotational direction or the axial direction, or those By moving in two directions, the outer surface of the rotating cylindrical body having the cryotarget layer is moved in the plane direction with respect to the focused irradiation point of the spatially fixed pulse laser beam. Then, the focused irradiation point is relatively moved on the outer surface of the rotating cylindrical body, a high-temperature and high-density plasma is generated by the focused irradiation of the pulsed laser beam, and the plasma is generated by the focused irradiation of the pulsed laser beam. A laser plasma X-ray generator for repairing a cryo-target layer in which a crater hole is generated by the supply of the target material supplied from the target material supply port, and continuously generating pulse X-rays from the high-temperature high-density plasma In
A crystal fixing groove for depositing a target material is provided at a position on the outer surface of the rotating cylindrical body where the pulsed laser beam is condensed and irradiated, and the target material supply port is configured to supply the target material toward the crystal fixing groove. And place
Around the outer surface of the rotating cylinder at a position beyond the both ends in the axial direction of the crystal fixing groove on the outer surface of the rotating cylinder on both sides in the axial direction across the target material supply port on the inner surface of the cover A laser plasma X-ray generator characterized in that a pointed annular projection is provided which forms orifices and substantially seals a space defined by the orifices on both sides in the axial direction. The laser plasma X-ray generator according to claim 2, wherein the cover is disposed in a vacuum chamber. A plurality of partitions are provided in which a space defined on both sides in the axial direction by the orifice is divided into a plurality of spaces in a circumferential direction so that each of the plurality of spaces is substantially sealed, and the target material supply ports are respectively provided to the plurality of spaces. 4. The laser plasma X-ray generator according to claim 3, wherein the apparatus is arranged.

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