Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to techniques employed to control a projector in a projection image display apparatus when a light source unit or a filter of genuine/non-genuine products are used therein. 
     2. Description of the Background Art 
     Projectors configured with a projector light source comprising a lamp for a light source and a reflection umbrella surrounding the lamp, with the lamp exchangeable with a lamp of a different type and combined with an initially used reflection umbrella to allow the lamps to be exchanged, are known from Japanese Patent Laying-open Nos. 2000-131758 and 2000-131759. 
     In doing so, information corresponding to the type of the exchanged lamp can be obtained and in accordance therewith a drive voltage and a cooling operation can be controlled in accordance with the lamp&#39;s different specification. 
     Furthermore, this configuration also allows information of an illumination unit corresponding to the lamp to be obtained, and a lamp having any rating can be driven. 
     As disclosed in prior art, the techniques for control described in the above documents are effective for a specification of an identified component and a component of a genuine product of a manufacturer that satisfies safety for cooling. Currently, however, components of non-genuine products that manufacturers are not involved in are also in the market. 
     Accordingly, there is a possibility that such non-genuine light sources or non-genuine filters cannot be verified by manufacturers sufficiently and there is a possibility that users who use non genuine light sources or non genuine filters may have unexpected disbenefits. 
     SUMMARY OF THE INVENTION 
     The present invention contemplates a projection image display apparatus including a detachably attachable light source or filter, that does not disbenefit users who use non genuine light sources or non genuine filters in the apparatus. 
     The present invention in one aspect provides a projection image display apparatus comprising: a light source unit configured to be detachably attachable to a main body of the apparatus; a storage unit provided to the light source unit for previously storing therein information that the light source unit is a genuine product; a determination unit communicatively connected to the storage unit in response to the light source unit being attached to the main body of the apparatus for communicating with the storage unit using the information to make a decision on whether the light source unit is the genuine product; and a light source control unit operative in accordance with the decision made by the determination unit to control an output of the light source unit. 
     The present invention in another aspect provides a projection image display apparatus comprising: a light source unit configured to be detachably attachable to a main body of the apparatus; a cooling unit for cooling the light source unit; a storage unit provided to the light source unit for previously storing therein information that the light source unit is a genuine product; a determination unit communicatively connected to the storage unit in response to the light source unit being attached to the main body of the apparatus for communicating with the storage unit using the information to make a decision on whether the light source unit is the genuine product; and a cooling control unit operative in accordance with the decision made by the determination unit to control an output of the cooling unit. 
     The present invention in still another aspect provides a projection image display apparatus comprising: a light source unit configured to be detachably attachable to a main body of the apparatus; an optical modulation unit modulating light received from the light source unit; a projection lens receiving light from the optical modulation unit and magnifying and projecting the light on a screen; a storage unit provided to the light source unit for previously storing therein information that the light source unit is a genuine product; a determination unit communicatively connected to the storage unit in response to the light source unit being attached to the main body of the apparatus for communicating with the storage unit using the information to make a decision on whether the light source unit is the genuine product; and an OSD device for displaying on a screen the decision made by the determination unit. 
     The present invention in still another aspect provides a projection image display apparatus comprising: a light source unit; a filter disposed on a coolant channel passing a coolant therethrough for cooing the light source unit, and configured to be detachably attachable to a main body of the apparatus; an optical modulation unit modulating light received from the light source unit; a projection lens receiving light from the optical modulation unit and magnifying and projecting the light on a screen; a storage unit provided to the filter for previously storing therein information that the filter is a genuine product; a determination unit communicatively connected to the storage unit in response to the filter being attached to the main body of the apparatus for communicating with the storage unit using the information to make a decision on whether the filter is the genuine product; and an OSD device for displaying on a screen the decision made by the determination unit. 
     Preferably, when the determination unit determines that the light source unit is a non genuine product the light source control unit decreases the output of the light source unit to be smaller than in a normal operation. 
     Preferably, when the determination unit determines that the light source unit is a non genuine product the cooling control unit increases the output of the cooling unit to be larger than in a normal operation. 
     Preferably, when the determination unit determines that the light source unit is a non genuine product the OSD device operates to display on the screen that the light source unit is the non genuine product. 
     Preferably, when the determination unit determines that the filter is a non genuine product the OSD device operates to display on the screen that the filter is the non genuine product. 
     The present invention can thus provide a projection image display apparatus including a detachably attachable light source or filter, that does not disbenefit users who use non genuine light sources or non genuine filters in the apparatus. 
     The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a configuration of an optical engine of a projection image display apparatus according to a first embodiment. 
         FIGS. 2A and 2B  are perspective views of a detachably attachable light source of the projection image display apparatus according to the first embodiment. 
         FIG. 3  is a perspective view of a light source according to the first embodiment. 
         FIG. 4  is a block diagram of a configuration detecting whether a light source is a genuine product according to the first embodiment. 
         FIG. 5  is an example of an OSD displayed according to the first embodiment. 
         FIG. 6  is a flowchart of an operation according to the first embodiment. 
         FIGS. 7A and 7B  are perspective views of a detachably attachable filter of a projection image display apparatus according to a second embodiment. 
         FIG. 8  is a block diagram of a configuration detecting whether a filter is a genuine product according to the second embodiment. 
         FIG. 9  is an example of an OSD displayed according to the second embodiment. 
         FIG. 10  is a flowchart of an operation according to the second embodiment. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made to  FIGS. 1-10  to describe a projection image display apparatus according to each embodiment of the present invention. 
     It should be noted that the figures are schematic and specific geometries, dimensions, and ratios are different. Furthermore, some specific geometries, dimensions, and ratios are also different between the figures. 
     Furthermore, in the figures, identical or similar components are identically denoted and will not be described repeatedly. 
     First Embodiment 
     The present invention in a first embodiment provides a projection image display apparatus, as will now be described hereinafter with reference to  FIGS. 1-6 . 
       FIG. 1  shows a 3-plate liquid crystal optical engine  1  in the first embodiment. In a light source  2  a light emitting unit is a super high pressure mercury lamp, a metal halide lamp, a xenon lamp or the like, and emits light which is in turn collimated by a parabola reflector  3  and thus emanates therefrom, and is guided to an integrator lens  4 . 
     Integrator lens  4  is configured of a pair of lenses (fly eye lens)  4   a  and  4   b . Each lens portion is adapted to guide the light that emanates from light source  2  to an entire surface of a liquid crystal light valve described hereinafter, to average partial, varying intensity present in light source  2  to reduce a difference in quantity of light between a center of a screen and a peripheral portion of the screen. Integrator lens  4  passes light, which in turn passes through a polarization conversion device  5  and a condenser lens  6  and is then guided to a first dichroic mirror  7 . 
     Polarization conversion device  5  is configured of a polarizing beam splitter array (hereinafter referred to as “PBS array”). The PBS array includes a polarization separating film and a phase difference plate (a ½λ plate). The PBS array&#39;s each polarization separating film receives light from integrator lens  4  and, of the received light, for example transmits p polarized light and redirects s polarized light to have an optical path changed by 90°. The s polarized light having its optical path changed is reflected by an adjacent polarization separating film and thus emanates. In contrast, the p polarized light transmitted through the polarization separating film is converted to s polarized light by the phase difference plate provided at a front side of the p polarized light (i.e., a side at which the light emanates), and thus emanates. In other words, in this case, almost all of light is converted to s polarized light. 
     First dichroic mirror  7  transmits red color wavelength band light and reflects cyan (green plus blue) wavelength band light. The red color wavelength band light transmitted by first dichroic mirror  7  is reflected by a total reflection mirror  8  and thus has its optical path changed. The red color light reflected by total reflection mirror  8  passes through a lens  9  and is transmitted through a transmission liquid crystal light valve  31  for red color light and thus optically modulated. The cyan wavelength band light reflected by first dichroic mirror  7  is guided to a second dichroic mirror  10 . 
     Second dichroic mirror  10  transmits blue color wavelength band light and reflects green wavelength band light. The green wavelength band light reflected by second dichroic mirror  10  passes through a lens  11  and is guided to a transmission liquid crystal light valve  32  for green color light, and transmitted therethrough and thus optically modulated. The blue wavelength band light transmitted by second dichroic mirror  10  is guided via total reflection mirrors  12  and  13  and a lens  14  to a transmission liquid crystal light valve  33  for blue color light, and transmitted therethrough and thus optically modulated. 
     Each liquid crystal light valve  31 ,  32 ,  33  is an optical modulation unit including incident polarization plates  31   a ,  32   a ,  33   a , panel units  31   b ,  32   b ,  33   b  formed of a pair of glass substrates (provided with a pixel electrode, an orientation film and the like) and liquid crystal sealed between the glass substrates, and emanating polarization plates  31   c ,  32   c ,  33   c.    
     The light modulated through liquid crystal light valves  31 ,  32 ,  33  (or the light of each color of an image) is composited by a cross dichroic prism  15  to be colored image light, which is in turn magnified by a projection lens  16  and thus projected, and thus displayed on a screen (not shown). 
       FIGS. 2A and 2B  are perspective views of a projection image display apparatus of the present invention in the first embodiment implemented as a projector  20 . 
     Furthermore,  FIG. 2A  shows projector  20  with a back case  21  drawn out frontward, and  FIG. 2B  shows projector  20  with back case  21  drawn out frontward and a light source unit  22  therein extracted therefrom. 
     Projector  20  has a casing  28 , which is provided with an optical engine  1 , a main board (not shown), a cooling fan  45  (see  FIG. 4 ), ventilation holes  23  and  24 , an external equipment connector unit  25 , a console panel  26 , and the like. 
     The main board (not shown) is powered on by a user to operate to variously control projector  20 , such as an optical modulation function by optical engine  1 , executing a specific operation performed by the user, transmitting/receiving and converting a signal received from and output to external equipment connector unit  25 . 
     Cooling fan  45  introduces external air through ventilation holes  23 ,  24  and the like to cool a heat generating portion of light source  2  or the like, and exhausts externally from projector  20  the air that has cooled the portion. 
     External equipment connector unit  25  is a unit interfacing with external image equipment and is provided with a variety of connectors to accommodate a variety of specifications. 
     Back case  21  is a portion of casing  28 , and disengaging a screw  27  to open the case allows the case to expose light source unit  22 . 
       FIG. 3  is a perspective view of light source unit  22  of the present invention in the first embodiment. Light source unit  22  includes a light source  2 , a lamp housing  30 , a handle  31 , protection glass  32 , a light source connector  33 , an authentication IC  34 , and an authentication IC connector  35 . 
     Light source  2  is housed in lamp housing  30  and receives electric power through light source connector  33  to emit light of high intensity. Furthermore, as it is repeatedly used, light source  2  decreases in intensity and thus reaches the end of its life. Accordingly, after it is used for a period of time, light source  2  needs to be exchanged with a new light source. 
     Lamp housing  30  is formed to position light source  2  and is preferably formed of a heat resistant resin which is capable of enduring the heat of light source  2  increased in temperature and also has low thermal conductivity. 
     Handle  31  is provided at an upper surface of lamp housing  30  and formed to allow light source unit  22  to be easily held and extracted when back case  21  is opened. 
     Protection glass  32  prevents a user from touching light source  2  generating heat. 
     Light source connector  33  electrically connects the main board and light source  2 , and light source connector  33  thus connected allows light source  2  to receive power supply. 
     Authentication IC  34  is connected by authentication IC connector  35 , which is disposed in a vicinity of light source connector  33  and configured of a power supply line and two communication lines provided for authentication IC  34 , on a IIC bus or the like to a host CPU  40  (see  FIG. 4 ), which is incorporated in the main board, to identify light source unit  22 . 
     Light source connector  33  and authentication IC connector  35  will be connected to a connector that is provided at the main board when a guidance mechanism (not shown) inserts light source unit  22  into projector  20 . 
       FIG. 4  is a block diagram of a configuration detecting whether a light source is a genuine product according to the first embodiment of the present invention. 
     When projector  20  is powered on and thus activated, host CPU  40  provided at the main board is simultaneously activated. 
     Host CPU  40  exerts control to perform a predetermined operation performed when an optical modulation unit  41 , a light source driver  42 , a fan driver  43 , and an OSD generation unit  44  normally operate. 
     Herein, OSD is an abbreviation of “on-screen display” and is and will also be used hereinafter as a general term for displaying characters, symbols or the like on an image screen to notify a user of information of equipment or the like. 
     Furthermore, when host CPU  40  is activated, it initially transmits a sequence of random numbers to authentication IC  34 . Authentication IC  34  receives the sequence of random numbers, and calculates an exclusive OR of the received sequence of random numbers with an encryption key sequence for encryption and returns it to host CPU  40 . Host CPU  40  receives the encrypted, returned signal, and calculates an exclusive OR with the encryption key sequence to reconstruct the returned signal. 
     The initial sequence of random numbers is compared with the reconstructed sequence of numbers and if they match, host CPU  40  can determine that light source unit  22  currently used is a genuine product, and host CPU  40  issues an instruction to optical modulation unit  41 , light source driver  42  and fan driver  43  to normally operate. 
     In contrast, if the initial sequence of random numbers and the reconstructed sequence of numbers do not match, host CPU  40  can determine that light source unit  22  currently used is a non genuine product, and host CPU  40  issues an instruction to light source driver  42  to cause light source  2  to provide a reduced quantity of light, an instruction to fan driver  43  to cause cooling fan  45  to attain a maximum output level, and an instruction to OSD generation unit  44  to generate an OSD indicating that the light source unit is not a genuine product of a manufacturer. Preferably, host CPU  40  makes a comparison with a specification of a light source unit of a genuine product and issues an instruction to light source driver  42  to provide a quantity of light estimated to be a minimum output level. 
     Furthermore, authentication IC  34  is preferably for example an IC of a non general purpose product to prevent non genuine products from easily imitating it. 
     When it is preferable to issue notification to a user involved in projector  20 , OSD generation unit  44  generates and transmits a predetermined phrase, symbol and/or the like to optical modulation unit  41  to display it as an OSD together with an image or alone via projection lens  16  (see  FIG. 5 ). 
       FIG. 6  is a flowchart of an operation according to the first embodiment of the present invention. 
     Projector  20  is powered on (S 1 ), and in response, light source unit  22  is identified for whether it is a genuine product or a non genuine product (S 3 ). 
     If light source unit  22  is a genuine product (YES at S 3 ), it is less likely to cause a failure, and each component configuring projector  20  is normally operated (S 5 ). If light source unit  22  is a non genuine product (NO at S 3 ), there is a possibility that the light source may cause an unexpected failure. Accordingly, light source driver  42  decreases the output of light source  2  (S 7 ). 
     After S 7 , similarly as described above, fan driver  43  provides adjustment to cause cooling fan  45  to provide a maximum output in preparation for heat generated by light source  2  unexpectedly (S 9 ). 
     After S 9 , an OSD is displayed to inform the user that light source unit  22  currently used is a non genuine product (S 11 ). 
     Note that while in the  FIG. 6  flowchart, S 7  is followed by S 9  followed by S 11 , these steps may not be performed in a fixed order or may be performed concurrently. Furthermore, only one of S 7 , S 9 , S 11  may be performed, or two or more of S 7 , S 9 , S 11  may be combined together and thus performed. 
     Furthermore, the  FIG. 6  flowchart describes that whether light source unit  22  is a genuine product or not is identified when projector  20  is powered on (S 1 ). Alternatively, whether light source unit  22  is a genuine product or not may be identified when light source unit  22  is attached to the main body of the apparatus. 
     Effect of First Embodiment 
     Hopefully, a light source that is a genuine product of a manufacturer that satisfies a specification of a component, safety for cooling, and the like should be used. If a light source that is not a manufacturer&#39;s genuine product is used, however, the manufacturer cannot provide sufficient verification thereon for safety or exert control in accordance with that lamp. In such a situation, using the non genuine product can invite an unexpected failure, and more specifically, there is a possibility that the light source may abnormally generate heat, which may in turn damage an optical component, a mechanism component and the like other than the light source. 
     The configuration of the first embodiment can reduce the light source&#39;s abnormal heat generation as well as the possibility that the light source&#39;s abnormal heat generation invites a secondary damage to damage an optical component, a mechanism component and the like other than the light source. 
     Furthermore, while it is also possible to prevent using non genuine products, the configuration of the first embodiment allows a user necessitated to temporarily use a non genuine product to use it, and a disbenefit to the user can thus be avoided at least at a lowest level. 
     Second Embodiment 
     Hereinafter reference will be made to  FIG. 7  to  FIG. 10  to describe a projection image display apparatus of the present invention in a second embodiment. 
     In the first embodiment, whether light source unit  22  is a genuine product or a non genuine product is determined. In the second embodiment, whether a filter  60 , rather than light source unit  22 , is a genuine product or a non genuine product is determined. 
     If filter  60  currently used is a genuine product, it satisfies a specification of a component, safety for cooling, and the like, and the normal operation is less likely to cause a problem. 
     If filter  60  currently used is a non genuine product, then there is one possibility that it has an insufficient ability to introduce sufficient air to cool a heat generating portion. Accordingly, an OSD is displayed to inform that filter  60  is a non genuine product. There is also another possibility that filter  60  has an insufficient ability to collect dust. Accordingly, an OSD is displayed to inform that filter  60  is a non genuine product. 
       FIGS. 7A and 7B  are perspective views of projector  20  implementing the projection image display apparatus according to the second embodiment of the present invention. 
     Furthermore,  FIG. 7A  shows projector  20  such that a side cover  61  housing filter  60  is opened, and  FIG. 7B  shows projector  20  with filter  60  extracted. 
     Filter  60  is detachably attached on a ventilation path connecting a ventilation hole  62  and a heat generating component, and includes a filter film  63  blocking a flow path. Filter film  63  has a function to prevent fine dust and the like from passing therethrough and pass air therethrough. 
     Filter  60  can thus remove fine dust included in external air introduced through ventilation hole  62  and prevent dust from adhering to an optical component and the like, and also allows a heat generating component to be cooled. 
     Furthermore, as filter  60  functions to remove dust and the like, it has dust and the like deposited thereon as it is used for a long period of time. The deposited dust prevents external air from flowing in and thus contributes to a reduced amount of external air introduced. Accordingly in view of protecting a heat generating component it is necessary to exchange filter  60  on a regular basis. 
       FIG. 8  is a block diagram of a configuration detecting whether a filter is a genuine product according to the second embodiment of the present invention. 
     In contrast to the first embodiment, filter  60  and authentication IC  34  provided to filter  60  are introduced. 
     When host CPU  40  is activated, it initially transmits a sequence of random numbers to authentication IC  34 . Authentication IC  34  receives the sequence of random numbers, and calculates an exclusive OR of the received sequence of random numbers with an encryption key sequence for encryption and returns it to host CPU  40 . Host CPU  40  receives the encrypted, returned signal, and calculates an exclusive OR with the encryption key sequence to reconstruct the returned signal. 
     The initial sequence of random numbers is compared with the reconstructed sequence of numbers and if they match, host CPU  40  can determine that filter  60  currently used is a genuine product, and host CPU  40  issues an instruction to optical modulation unit  41  and light source driver  42  to normally operate. 
     In contrast, if the initial sequence of random numbers and the reconstructed sequence of numbers do not match, host CPU  40  can determine that filter  60  currently used is a non genuine product, and host CPU  40  issues an instruction to OSD generation unit  44  to generate and display an OSD indicating that the filter is not a genuine product of a manufacturer (see  FIG. 9 ). 
     Furthermore, authentication IC  34  is preferably for example an IC of a non general purpose product to prevent non genuine products from easily imitating it. 
       FIG. 10  is a flowchart of an operation according to the second embodiment of the present invention. 
     Projector  20  is powered on (S 21 ), and in response, filter  60  is identified for whether it is a genuine product or a non genuine product (S 23 ). 
     If filter  60  is a genuine product (YES at S 23 ), it is less likely to cause a failure, and each component configuring projector  20  is normally operated (S 25 ). If filter  60  is a non genuine product (NO at S 23 ), an OSD is displayed to inform the user that filter  60  currently used is a non genuine product (S 27 ). 
     Furthermore, the  FIG. 10  flowchart describes that whether filter  60  is a genuine product or not is identified when projector  20  is powered on (S 21 ). Alternatively, whether filter  60  is a genuine product or not may be identified when filter  60  is attached to the main body of the apparatus. 
     Effect of Second Embodiment 
     Hopefully, a filter that is a genuine product of a manufacturer that satisfies a specification of a component, safety for cooling, and the like should be used. If a filter that is not a manufacturer&#39;s genuine product is used, however, it can invite an unexpected failure, and more specifically, there is a possibility that the light source may abnormally generate heat, which may in turn damage an optical component, a mechanism component and the like other than the light source, or the optical component may suffer dust adhering thereto. 
     The configuration of the second embodiment can inform a user before the light source abnormally generates heat, which may in turn invite a secondary damage to damage an optical component, a mechanism component and the like other than the light source, or the optical component has dust adhering to. The configuration of the second embodiment can thus provide an opportunity to obviate such problems. 
     Furthermore, while it is also possible to prevent using non genuine products, the configuration of the second embodiment allows a user necessitated to temporarily use a non genuine product to use it, and a disbenefit to the user can thus be avoided at least at a lowest level. 
     Note that in the first embodiment when light source unit  22  is a non genuine product, light source  2  is controlled to provide an output of a reduced level. Alternatively, light source  2  may completely be turned off. This can also reduce the possibility that the light source may abnormally generate heat, which may in turn invite a secondary damage to damage an optical component, a mechanism component and the like other than the light source. 
     Furthermore in the first or second embodiment when light source unit  22  or filter  60  is a non genuine product an OSD is displayed to indicate that it is a non genuine product. However, light source connector  33  or a filter connector may insufficiently be connected, and accordingly, an OSD that so indicates may also be provided. 
     Furthermore, while the first or second embodiment has indicated a projection image display apparatus employing a liquid crystal display panel, the present invention is not limited thereto, and is applicable to a projection image display apparatus including a different type of image light generation system, and can also be applied in the DLP (Digital Light Processing) system, a registered trademark of Texas Instruments Incorporated, and the LCOS (Liquid Crystal on Silicon) system. 
     It should be noted that in the above description, authentication IC  34  corresponds in the present invention to an embodiment of a storage unit and host CPU  40  corresponds in the present invention to an embodiment of a determination unit or a determination means. Furthermore, light source driver  42  corresponds in the present invention to an embodiment of a light source control unit or a light source control means. Furthermore, cooling fan  45  corresponds in the present invention to an embodiment of a cooling unit and fan driver  43  corresponds in the present invention to an embodiment of a cooling control unit or a cooing control means. Furthermore, OSD generation unit  44  corresponds in the present invention to an embodiment of an OSD device. 
     Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the scope of the present invention being interpreted by the terms of the appended claims.

Technology Category: 3