Projector structure and laser projection imaging equipment

Abstract

The present application is applicable to the technical field of laser projection equipment, and provides a projector structure and laser projection imaging equipment. The projector structure includes a laser module, a light concentrator and a light combining component. The laser module is provided with a plurality of light modules, each of which is used to emit light; the light concentrator is provided on the light-emitting side of the laser module, and is used to receive and focus the light emitted by the laser module; the light combining component is provided on the light-emitting side of the light concentrator, and is used to receive the light passing through the light concentrator, and mix the light passing through the light concentrator evenly. In the projector structure provided by the present application, the light emitted by a plurality of laser modules is focused by the light concentrator, and then the light focused by the light concentrator is evenly mixed by the light combining component, and then emitted, so that a plurality of laser modules can be combined and integrated through a beam combining module, which reduces the occupied space and makes the product smaller.

Description

Technical Field

[0001] The present application relates to the technical field of laser projection equipment, and more specifically, to a projector structure and a laser projection imaging device. Background Art

[0002] At present, laser projection, also known as laser projection display, is a display technology that uses red, green and blue (RGB) three-primary color lasers as light sources. It can reproduce the rich and gorgeous colors of the objective world in the most realistic way and provide more shocking expression. It is an important technological innovation in the projection industry. However, in the existing technology, in conventional laser light source equipment, a group of RGB laser tubes will correspond to a beam combining module, that is, each laser module requires a beam combining module, resulting in a large space occupied by the module, thereby increasing the size of the projector. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a projector structure, aiming to solve the technical problem in the prior art that each laser module in the laser light source equipment requires a beam combining module, resulting in the block occupying a large space.

[0004] To achieve the above purpose, the technical solution adopted by the present application is: to provide a projector structure, including:

[0005] A laser module, wherein a plurality of laser modules are provided, and each laser module is used for emitting light;

[0006] A light focusing member, which is disposed on the light-emitting side of the laser module and is used to receive and focus the light emitted by the laser module;

[0007] A light combining component is arranged on the light emitting side of the light concentrating component, and is used to receive the light passing through the light concentrating component and mix the light passing through the light concentrating component evenly.

[0008] Furthermore, the projection mechanism also includes digital micro-mirrors, the number of which is the same as the number of the laser modules, which are arranged on the light-emitting side of the light-combining component and are used to receive the light from the laser modules through the light-combining component in a one-to-one correspondence.

[0009] Further, the laser module includes three laser tubes of different colors;

[0010] A strip reflector, which is arranged on the light-emitting side of the laser tube, is used to emit the light emitted by the laser tube, and is arranged one-to-one with the laser tube;

[0011] The adjustable reflector is used to receive the light emitted by the long reflector and to emit the received light emitted by the long reflector.

[0012] Furthermore, a plurality of laser tubes of the same color are provided, and laser tubes of different colors are arranged adjacent to each other.

[0013] Furthermore, there is a preset difference between the wavelengths of light emitted by the plurality of laser tubes of the same color.

[0014] Furthermore, a lens is arranged between the long reflector and the adjustable reflector.

[0015] Furthermore, the projector structure also includes a shaping element, which is arranged between the laser module and the focusing element, and is used to receive the light from the laser module and perform collimation, convergence or parallelization processing on the light from the laser module.

[0016] Further, the shaping element is a collimator; or

[0017] The shaping element is a convex lens; or

[0018] The shaping element is a concave lens;

[0019] The light focusing element is a convex lens; and / or

[0020] The light combining component is a light rod.

[0021] Furthermore, the projection mechanism further comprises:

[0022] A water cooling module provided on the laser module, the water cooling module being used to cool the laser module;

[0023] A temperature control module, the temperature control module is electrically connected to the water cooling module and is used to control the operation of the water cooling module;

[0024] A wavelength control module is electrically connected to the laser module and is used to control the wavelength of light emitted by the laser module.

[0025] The present application also provides a laser projection imaging device, comprising the projector structure described in any of the above embodiments.

[0026] The beneficial effect of the projector structure provided by the present application is that compared with the prior art, in the projector structure of the present application, the light emitted by multiple laser modules is focused by a focusing element, and then the light focused by the focusing element is evenly mixed by a light combining element and then emitted. Multiple laser modules can be combined and integrated through a beam combining module, thereby reducing the occupied space and making the product smaller. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 It is a schematic structural diagram of an implementation scheme of a projector structure provided by an embodiment of the present application;

[0029] Figure 2 It is a schematic diagram of an implementation of a laser module of a projector structure provided by an embodiment of the present application;

[0030] Figure 3 It is a schematic diagram of an implementation of a laser module of a projector structure provided by an embodiment of the present application;

[0031] Figure 4 A schematic diagram of another implementation of a projector structure provided by an embodiment of the present application;

[0032] Figure 5 It is a structural schematic diagram of another implementation of a projector structure provided by an embodiment of the present application;

[0033] Figure 6 This is a schematic diagram of another implementation structure of a projector structure provided by an embodiment of the present application.

[0034] The reference numerals in the above drawings are as follows:

[0035] 1-laser module; 2-light focusing element; 3-light combining element; 4-digital micro-mirror; 5-shaping element; 6-temperature control module; 7-wavelength control module;

[0036] 11-laser tube; 12-long reflector; 13-adjustable reflector; 14-lens;

[0037] 111-red laser tube; 112-green laser tube; 113-blue laser tube;

[0038] 31- first light stick; 32- second light stick. DETAILED DESCRIPTION

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0040] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0041] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0042] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0043] It should be noted that the "optical element" in the present application may refer to an element that acts on light, for example, a convex lens with a converging effect, a plane mirror with a reflecting effect, a prism with a refracting effect, etc. For the selection of specific optical elements, technical personnel in this field can make a choice according to actual needs.

[0044] In order to illustrate the technical solution described in this application, a detailed description is given below in conjunction with specific drawings and embodiments.

[0045] Please refer to Figure 1 and Figure 4 As shown, an embodiment of the present application provides a projector structure, including a laser module 1, a focusing element 2 and a light combining element 3, wherein a plurality of laser modules 1 are provided, and each of the laser modules 1 is used to emit light, such as red, blue and green light respectively; the focusing element 2 is provided on the light-emitting side of the laser module 1, and is used to receive and focus the light emitted by the laser module 1; the light combining element 3 is provided on the light-emitting side of the focusing element 2, and is used to receive the light passing through the focusing element 2, and to mix and evenly process the light passing through the focusing element 2.

[0046] In some embodiments of the present application, the light emitted by each laser module 1 may be the same or different. For example, the laser modules 1 may all emit red light, or may all emit blue light, or may all emit green light; or, when there are six laser modules 1, two of the laser modules 1 emit red light, the other two of the laser modules 1 emit green light, and the laser module 1 emits blue light; or, when there are six laser modules 1, three of the laser modules 1 emit red light, the other two of the laser modules 1 emit blue light, and the other of the laser modules 1 emits green light. That is, those skilled in the art may set the number of the laser modules 1 and the color of the light emitted by each laser module 1 according to actual needs.

[0047] In some embodiments of the present application, the light concentrator 2 may be an optical element, or an optical element group consisting of a plurality of optical elements. For example, the light concentrator 2 may be a convex lens, or an optical element group consisting of a convex lens, a concave lens, and a convex lens arranged in sequence. The specific structure of the light concentrator 2 may be set according to actual needs, as long as it can converge light, and is not limited here.

[0048] In some embodiments of the present application, the light combiner 3 may be an optical element, or an optical element group composed of multiple optical elements. For example, the light combiner 3 may be a light rod, or the light combiner 3 may be an optical element group composed of a homogenizer and a light rod. The specific structure of the light combiner 3 may be set according to actual needs, and is not limited here as long as the light can be mixed. In the projector structure provided in the embodiments of the present application, the light emitted by the multiple laser modules 1 is focused by the light focusing element 2, and then the light focused by the light focusing element 2 is evenly mixed by the light combining element 3, and then emitted. For example, please refer to Figure 1 and Figure 4 As shown, there are two laser modules 1, each of which emits red light, green light and blue light. After the red light, green light and blue light of each laser module 1 are focused by the focusing element 2 respectively, the focusing element 2 can use a convex lens to focus, and then emit them to the light combining element 3. The light combining element 3 mixes the red light, green light and blue light. The light combining element 3 can use a light rod to mix the red light, green light and blue light. These lights will undergo multiple total reflections in the light rod, thereby playing a role in evenly mixing the red light, green light and blue light, thereby realizing the integration of light beams. In this way, multiple laser modules 1 can be combined and integrated through a beam combining module, reducing the occupied space and making the product smaller.

[0049] In some embodiments of the present application, optionally, please refer to Figure 1 and Figure 4As shown, the projection mechanism further includes digital micro-mirrors 4 , the number of which is the same as the number of the laser modules 1 , which are arranged on the light-emitting side of the light-combining component 3 and are used to receive the light from the laser module 1 through the light-combining component 3 in a one-to-one correspondence.

[0050] In this embodiment, the same number of digital micro-mirrors (DMD) as the number of laser modules 1 are arranged on the light-emitting side of the light-combining element 3. The digital micro-mirror 4 (DMD) is an array composed of a plurality of high-speed digital light-reflecting switches, and is composed of many small aluminum reflective mirrors. The number of mirrors is determined by the display resolution, and a small mirror corresponds to one pixel. For example, there are two groups of laser modules 1, one of which is a laser module 1 and the other is b laser module 1. A digital micro-mirror 4 a and a digital micro-mirror b 4 are arranged correspondingly, so that the light of the a laser module 1 after passing through the light-combining element 3 is incident on the a digital mirror 4, and the light of the b laser module 1 is incident on the b digital micro-mirror 4, and then the digital micro-mirror 4 reflects it to the optical processing system of the projector, and then performs imaging and projection. The purpose of using two digital micro-mirrors 4 (DMD) is to generate left-eye and right-eye views respectively, and then to be used for 3D image projection.

[0051] In some embodiments of the present application, optionally, please refer to Figure 2 and Figure 3 As shown, the laser module 1 includes three laser tubes 11 of different colors;

[0052] A long reflector 12, which is arranged on the light-emitting side of the laser tube 11, used to emit the light emitted by the laser tube 11, and is arranged one-to-one with the laser tube 11;

[0053] The adjustable reflector 13 is used to receive the light emitted by the long reflector 12 and to reflect the received light emitted by the long reflector 12 .

[0054] In this embodiment, each laser module 1 includes a red laser tube 111, a green laser tube 112 and a blue laser tube 113. The light emitted from the red laser tube 111, the green laser tube 112 and the blue laser tube 113 is respectively reflected by the long reflector 12 to the adjustable reflector 13, and then the adjustable reflector guides and reflects the above light beams to the focusing element 2, that is, the reflection is transmitted to the convex lens to realize the combined transmission of light. In the prior art, it is generally composed of a plurality of groups of lens elements combined with a spectroscope, and the space occupied is larger than the structure of the above-mentioned long reflector 12 and the adjustable reflector of the present application.

[0055] In the above embodiments of the present application, optionally, please refer to Figure 3As shown, a lens 14 is arranged between the long reflector 12 and the adjustable reflector 13, wherein the lens 14 can be a convex lens, a concave lens or a combination thereof, or a convex lens of other shapes, so that the light reflected by the long reflector 12 passes through the lens 14 again and is transmitted to the adjustable reflector 13.

[0056] In the above embodiments of the present application, optionally, please refer to Figure 2 and Figure 3 As shown, a plurality of laser tubes 11 of the same color are provided, and the laser tubes 11 of different colors are arranged adjacent to each other.

[0057] In the present embodiment, it should be noted that a laser module 1 may include multiple groups of red laser tubes 111, green laser tubes 112, and blue laser tubes 113, and the order of the laser tubes 11 may be red laser tubes 111, green laser tubes 112, blue laser tubes 113, red laser tubes 111, green laser tubes 112, blue laser tubes 113, etc., and the arrangement may be repeated according to this rule.

[0058] In the above-mentioned embodiment of the present application, optionally, there is a preset difference between the wavelengths of light emitted by the plurality of laser tubes 11 of the same color.

[0059] In this embodiment, if there are two groups of laser modules 1, one of which is a laser module 1 and the other is b laser module 1, there is a certain difference in wavelength between the red laser tube 111 of laser module a and the red laser tube 111 of laser module b, and the wavelength difference between the two can be set to a preset difference, such as 20nm, and the wavelength between the green laser tube 112 of laser module a and the green laser tube 112 of laser module b also has a difference of 20nm, and the wavelength between the blue laser tube 113 of laser module a and the blue laser tube 113 of laser module b also has a difference of 20nm. The difference in wavelength causes the lens to have a difference in the refraction angle of the two laser modules 1, which in turn causes the optical path to be deviated. That is, due to the difference in wavelength, the reflection or refraction of the laser by the optical element will also be different. These differences lead to differences in the optical path. Therefore, the light of laser module a after passing through the light combiner 3 is incident on the digital reflector a 4, and the light of laser module b is incident on the digital micro reflector b 4.

[0060] In some embodiments of the present application, optionally, please refer to Figure 4 As shown, the projector structure further includes a shaping element 5, which is disposed between the laser module 1 and the focusing element 2, and is used to receive the light from the laser module 1, and to collimate, converge or parallelize the light from the laser module 1.

[0061] In this embodiment, optionally, the shaping element 5 is a collimator; or the shaping element 5 is a convex lens; or the shaping element 5 is a concave lens. In this technical solution, a shaping element 5 is added, and the shaping element 5 is used to adjust and optimize the laser beams emitted by two or more laser modules 1. The shaping element 5 can collimate or converge or parallelize the light of the laser module 1, for example, collimate the laser beam through a collimator, increase the convergence of the laser beam through a convex lens, increase the parallelism of the laser beam through a concave lens, etc., and then inject it into the focusing element 2 for focusing. The shaping element 5 can also be an optical element group composed of other optical elements such as the above-mentioned collimator, convex lens or concave lens, which will not be described one by one here.

[0062] In some embodiments of the present application, optionally, please refer to Figure 1 and Figure 4 As shown, the light focusing element 2 is a convex lens. The product structure can be simplified, and the light focusing effect can be ensured at the same time. In addition, the purchase cost is low, and the production is convenient and simple. It should be noted that the light focusing element 2 can be designed and selected according to actual needs, such as a spherical convex lens, an aspherical convex lens, a single-sided convex lens, a plano-convex lens, etc., which will not be described one by one here.

[0063] In some embodiments of the present application, optionally, please refer to Figure 1 and Figure 4 As shown, the light combining component 3 is a light rod, which is also called a homogenizing rod. The inner side of the homogenizing rod can totally reflect the light beam. After the light beam enters the homogenizing rod, it will undergo multiple total reflections, thereby playing the role of mixing the light beam evenly. At the same time, the light rod has a simple structure and is easy to install and manufacture.

[0064] In a specific embodiment of the present application, please refer to Figure 1 and Figure 4 As shown, there are two laser modules 1, one of which is a laser module 1 a, and the other is a laser module 1 b. The wavelengths of the same color light beams emitted by each laser module 1 have certain differences. The focusing component 2 adopts a convex lens, and the light combining component 3 adopts a light rod. Two digital micro-mirrors, such as a digital micro-mirror 4 and b digital micro-mirror 4, are arranged on the light-emitting side of the light rod. The light emitted by the a laser module 1 and the b laser module 1 is focused by the convex lens and then transmitted to the light rod for multiple total reflections to be evenly mixed. Then, the light of the a laser module 1 is emitted from the light rod to the a digital micro-mirror 4, and the light of the b laser module 1 is emitted from the light rod to the b digital micro-mirror 4. Then, multiple laser modules 1 can be combined and integrated through a beam combining module, with fewer optical components, simple structure, and reduced space occupied.

[0065] One embodiment of the present application provides a projector structure, such as Figure 5As shown, it includes a laser module 1, a focusing element 2 and a light combining element 3. The laser modules 1 are provided with three, and each of the laser modules 1 emits light, such as red, blue and green light respectively; the focusing element 2 is arranged on the light-emitting side of the laser module 1, and is used to receive and focus the light emitted by the laser module 1; the light combining element 3 is arranged on the light-emitting side of the focusing element 2, and is used to receive the light passing through the focusing element 2, and mix the light passing through the focusing element 2 evenly.

[0066] In some embodiments of the present application, the laser module 1 also includes a water cooling module arranged in the laser module 1. On the one hand, the water cooling module is used to cool the laser module 1, or cool the laser tube in the laser module 1; on the other hand, the water cooling module can also be used to maintain temperature stability, so that the working environment temperature of the laser module 1 fluctuates within a smaller range, thereby stabilizing the wavelength of light output by the laser module 1.

[0067] Specifically, the water cooling module can be arranged in the laser module 1. For example, the laser tube in the laser module 1 is arranged on a water cooling plate, the water cooling plate is connected to a circulating water cooling machine, the circulating water cooling machine cools the water cooling plate by cooling water, and the water cooling plate is used to transfer the heat generated by the laser tube when working.

[0068] Specifically, the water cooling module can be attached to the outside of the laser module 1. By cooling the outer shell of the laser module 1, the inside of the laser module 1 is cooled. For example, a semiconductor heat sink can be attached to the outside of the laser module 1.

[0069] Specifically, water cooling modules may be provided on both the inner side and the outer side of the laser module 1 .

[0070] It should be noted that the water cooling module can be a water cooler, or a fan, or a semiconductor heat sink, or other cooling structures, or a combination of multiple cooling structures. The specific structure of the water cooling module can be selected as needed and is not limited here.

[0071] In the above-mentioned embodiment of the present application, the laser module 1 also includes a temperature control module 6, which is electrically connected to the water cooling module. The temperature control module 6 and the water cooling module can send signals to each other, and the temperature control module 6 can control the water cooling module to achieve stable maintenance of the working environment temperature of the laser module 1.

[0072] It should be noted that the temperature control module 6 can be a single chip microcomputer, or a feedback circuit, or a central processing unit, etc. The specific structure of the temperature control module 6 can be selected as needed and is not limited here.

[0073] In some embodiments of the present application, the laser module 1 further includes a wavelength control module 7 , which is electrically connected to the laser module 1 , or to both the laser module 1 and the temperature control module 6 , and is used to control the wavelength of light emitted by the laser module 1 .

[0074] On the one hand, the wavelength control module 7 can control the wavelength of the light emitted by the laser module 1 by controlling the working voltage or the working current of the laser module 1 .

[0075] On the other hand, the wavelength control module 7 can also control the wavelength of the light emitted by the laser module 1 by controlling the working environment temperature of the laser module 1, that is, by controlling the working environment temperature of the laser module 1 through the temperature control module 6, thereby realizing the control of the wavelength of the light emitted by the laser module 1. This is because the wavelength of the light emitted by the laser module 1 will change with the change of temperature.

[0076] It should be noted that the wavelength control module 7 can be a single chip microcomputer, or a feedback circuit, or a central processing unit, etc. The specific structure of the wavelength control module 7 can be selected as needed and is not limited here.

[0077] In a specific embodiment of the present application, the first laser module 1 emits a laser beam of a first color, the second laser module 1 emits a laser beam of a second color, and the third laser module 1 emits a laser beam of a third color. The three laser beams of different colors are projected onto three different DMDs after passing through the focusing element 2 and the beam combining element 3, and after reflecting the three different DMDs, they are focused onto the same projection lens.

[0078] In a specific embodiment of the present application, Figure 6 As shown, the light combining member 3 includes a plurality of first light rods 31 and a second light rod 32. After passing through the light concentrating member 2, the light beam of each laser module 1 enters each first light rod 31 corresponding thereto respectively, and after being mixed by the first light rod 31, it converges to the second light rod 32. Because the laser beams in the laser module 1 are emitted by a plurality of laser tubes, the light beams of each laser module 1 are mixed by the first light rod 31 and then enter the second light rod 32 for mixing, which is conducive to uniform mixing of the laser beams.

[0079] In some embodiments of the present application, the projector structure further comprises a homogenizing plate, which is arranged on the light incident side of the light rod to enhance the light homogenizing effect of the light rod. The embodiment of the present application further provides a laser projection imaging device, comprising the projector structure described in any of the above embodiments.

[0080] In this embodiment, the laser projection imaging device has the projector structure provided by any of the above embodiments, and thus has all the beneficial effects of the projector structure, which will not be described in detail here.

[0081] To sum up, compared with the prior art, in the projector structure of the present application, the light emitted by multiple laser modules is focused by a focusing element, and then the light focused by the focusing element is evenly mixed by a light combining element before being emitted. This allows multiple laser modules to be combined and integrated through a beam combining module, thereby reducing the occupied space and making the product smaller.

[0082] The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A projector structure, characterized in that: include: A laser module, wherein a plurality of laser modules are provided, and each laser module is used for emitting light; A light focusing member, wherein the light focusing member is provided with one light focusing member, and the light focusing member is provided at the light emitting side of the plurality of laser modules, and is used for receiving the light emitted by the plurality of laser modules and focusing the light emitted by the plurality of laser modules; A light combining member, wherein the light combining member is provided with one light combining member, and the light combining member is provided at the light emitting side of the light concentrating member, and is used for receiving the light passing through the light concentrating member and mixing the light passing through the light concentrating member uniformly; The projector structure further includes a digital micro-mirror, the number of which is the same as the number of the laser modules, which is arranged on the light-emitting side of the light-combining component and is used to receive the light from the laser modules through the light-combining component in a one-to-one correspondence; Two of the digital micromirrors are used to generate left-eye and right-eye views respectively.

2. The projector structure according to claim 1, characterized in that: The laser module includes three laser tubes of different colors; A strip reflector, which is arranged on the light-emitting side of the laser tube, is used to emit the light emitted by the laser tube, and is arranged one-to-one with the laser tube; The adjustable reflector is used to receive the light emitted by the long reflector and to emit the received light emitted by the long reflector.

3. The projector structure according to claim 2, characterized in that: A plurality of laser tubes of the same color are provided, and laser tubes of different colors are arranged adjacent to each other.

4. The projector structure according to claim 3, characterized in that: There is a preset difference between the wavelengths of light emitted by the plurality of laser tubes of the same color.

5. The projector structure according to claim 2, characterized in that: A lens is arranged between the long reflector and the adjustable reflector.

6. The projector structure according to any one of claims 1 to 5, characterized in that: The projector structure also includes a shaping element, which is arranged between the laser module and the focusing element, and is used to receive the light from the laser module and perform collimation, convergence or parallelization processing on the light from the laser module.

7. The projector structure according to claim 6, characterized in that: The shaping element is a collimating lens; or The shaping element is a convex lens; or The shaping element is a concave lens; The light focusing element is a convex lens; and / or The light combining component is a light rod.

8. The projector structure according to claim 1, characterized in that: The projector structure also includes: A water cooling module provided on the laser module, the water cooling module being used to cool the laser module; A temperature control module, the temperature control module is electrically connected to the water cooling module and is used to control the operation of the water cooling module; A wavelength control module is electrically connected to the laser module and is used to control the wavelength of light emitted by the laser module.

9. A laser projection imaging device, characterized in that: Comprising the projector structure as claimed in any one of claims 1 to 8.

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