Patent Publication Number: US-10317675-B2

Title: Display device for motor vehicle

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National Phase application under 35 U.S.C. § 371 of International Application No. PCT/EP2015/064998, filed on Jul. 1, 2015, and claims benefit to French Patent Application No. FR 14/01483, filed on Jul. 1, 2014. The International Application was published in French on Jan. 7, 2016, as WO 2016/001313 A1 under PCT Article 21(2). 
     FIELD 
     The present invention relates to a display device, particularly for a motor vehicle. 
     BACKGROUND 
     Display devices of head-up display (HUD) type are known, notably with the projection of an image to a windshield as described in the document U.S. Pat. No. 5,214,413 or to a reflection element. 
     The display devices with head-up display make it possible to project information into the field of view of the space in front of the motor vehicle in order for the driver of the motor vehicle to be able to read this information without averting the eyes from the space in front of the motor vehicle. At the same time, the information can be read without modifying the focusing of the eyes of the driver of the vehicle. 
     It is advantageous according to the needs of a user of the vehicle for the display devices to be able to take account of several positions of the head (or of the eyes) of the user of the vehicle. 
     One drawback with such devices according to the prior art consists in the fact that the efforts to produce the link between the support element of a reflection and/or display element and the reflection and/or display element are relatively high, notably due to the fact that the stresses have to be low (so as not to deform the reflection and/or display element) while guaranteeing a good hold. 
     SUMMARY 
     In an exemplary embodiment, the invention provides a display device for a motor vehicle. The display device includes: a projection module for generating an image for a projection in a direction of gaze of a user of the display device along an optical path; a reflection and/or display element; a support element for the reflection and/or display element; and a holding element, configured such that the reflection and/or display element is held, without deformation of the reflection and/or display element, between the support element and the holding element and in a fixed position relative to the support element. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be described in even greater detail below based on the exemplary figures. The invention is not limited to the exemplary embodiments. All features described and/or illustrated herein can be used alone or combined in different combinations in embodiments of the invention. The features and advantages of various embodiments of the present invention will become apparent by reading the following detailed description with reference to the attached drawings which illustrate the following: 
         FIG. 1  is a schematic sectional view of a display device according to the present invention. 
         FIG. 2  is a schematic sectional view of a part of the display device according to the present invention with the reflection and/or display element. 
         FIGS. 3 to 9  are schematic perspective views or else detail views of the reflection and/or display element or of the link of the reflection and/or display element with the support element and/or the holding element. 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of the present invention provide a display device with head-up display having a reflection and/or display element which is linked to its support reliably and inexpensively. 
     In an exemplary embodiment, the present invention provides a display device, particularly for a motor vehicle, comprising a projection module for generating an image for a projection in the normal direction of gaze of a user of the display device along an optical path,
     the display device comprising a reflection and/or display element, and a support element for the reflection and/or display element,   characterized in that   the display device also comprising a holding element such that the reflection and/or display element is held, solidly, between the support element and the holding element and in a fixed position relative to the support element.   

     Through such an embodiment of a display device, it is advantageously possible to produce a link between the reflection and/or display element and its support element simply and inexpensively. Moreover, it is advantageously possible, according to the present invention, for a thermal decoupling to be produced to protect, on the one hand, the components (in particular electronic components) which are placed behind the reflection and/or display element relative to the thermal flux due to the incident light on the reflection and/or display element, and, on the other hand, to protect the reflection and/or display element (in particular relative to deformations due to an excessive overheating) from the thermal flux deriving from the components behind the reflection and/or display element. 
     In an exemplary embodiment, the reflection and/or display element and the support element are linked via first, second, third, fourth, fifth and sixth surfaces, the first, second and third surfaces being curved surfaces having a first radius, and the fourth, fifth and sixth surfaces being flat or curved surfaces having a second radius, the second radius corresponding to at least twice the first radius. 
     Through such an embodiment of the display device, it is advantageously possible to avoid material stresses in the material of the reflection and/or display element. 
     In an exemplary embodiment, each of the first, second and third surfaces corresponds to a surface of the fourth, fifth and sixth surfaces (in particular the first surface corresponds to the fourth surface and vice versa, the second surface corresponds to the fifth surface and vice versa, and the third surface corresponds to the sixth surface and vice versa). It is thus possible to produce a link between the reflection and/or display element and its support element simply and inexpensively. 
     In an exemplary embodiment, the reflection and/or display element and the holding element are linked via seventh, eighth, ninth, tenth, eleventh and twelfth surfaces, the seventh, eighth and ninth surfaces being curved surfaces having a third radius, and the tenth, eleventh and twelfth surfaces being flat or curved surfaces having a fourth radius, the fourth radius corresponding to at least twice the third radius. 
     Through such an embodiment of the display device, it is advantageously possible to avoid material stresses in the material of the reflection and/or display element. 
     In an exemplary embodiment, each of the seventh, eighth and ninth surfaces corresponds to a surface of the tenth, eleventh and twelfth surfaces (in particular the seventh surface corresponds to the tenth surface and vice versa, the eighth surface corresponds to the eleventh surface and vice versa, and the ninth surface corresponds to the twelfth surface and vice versa). It is thus possible to produce a link between the reflection and/or display element and the holding element simply and inexpensively. 
     In an exemplary embodiment, the holding element is fixed to the support element such that surfaces of the support element and of the holding element bear on corresponding surfaces of the reflection and/or display element, respectively. 
     In an exemplary embodiment, the reflection and/or display element comprises a main extension plane and two opposing sides, and the reflection and/or display element comprises at least one pair of surfaces on each side at corresponding locations. 
     In an exemplary embodiment, the first, second and third surfaces, and the tenth, eleventh and twelfth surfaces are surfaces of the reflection and/or display element, the fourth, fifth and sixth surfaces are surfaces of the support element, and the seventh, eighth and ninth surfaces are surfaces of the holding element. 
     In an exemplary embodiment, the reflection and/or display element are configured to be moved between a position of rest and at least one display position such that the reflection and/or display element is moved between its position of rest and its at least one display position via the support element. 
     Other features and advantages of the invention will emerge from reading the following description of a nonlimiting particular embodiment of the present invention. 
     As  FIG. 1  shows, a display device  10  according to the present invention comprises a projection module  11  which generates an image in the normal direction of gaze  15  of a user of the display device  10  along an optical path  12 . 
     The optical path  12  normally comprises at least one reflection and/or display element  13 . The optical path  12  can comprise a reflection element outside of the projection module  11  (as represented in  FIG. 1 ). According to the present invention, a reflection and/or display element  13  is typically incorporated in the projection module  11 . The optical path  2  can also comprise two reflection elements or two reflection and/or display elements, particularly with all incorporated in the projection module. 
     The normal direction of gaze  15  is the direction of view of a user of the display device  10 , notably a vehicle driver, when the latter is watching, notably through a windshield  14 , the outside which is located in front of the vehicle. 
     According to a preferred embodiment of the present invention, the reflection and/or display element  13  can be positioned in a position of rest and in at least one display position. When the reflection and/or display element  13  is positioned in its position of rest, the reflection and/or display element  13  is for example positioned inside a housing of the display device  10 , notably inside the projection module  11 . The position of the position of rest and of the display position of the reflection and/or display element  13  is changed through a rotational and/or translational movement. 
     The reflection and/or display element  13  has to be positioned relative to a housing, notably a projection module  11  which is called support element  16 . According to the present invention, a support element  16  or a support  16  is associated with the reflection and/or display element  13 . The support  16  or the support element  16  can be configured to be driven between different positioning states, notably via the motor element. 
     In  FIG. 2 , a perspective schematic view of a part of the display device (in particular the projection module  11 ) according to the present invention is shown with the reflection and/or display element  13  and the support element  16 . Moreover, a holding element  16 ′ is shown in  FIG. 2 . The reflection and/or display element  13  is positioned between the support element  16  and the holding element  16 ′. 
       FIGS. 3 to 9  show perspective schematic views and/or detail views of the reflection and/or display element or of the link of the reflection and/or display element with the support element and/or the holding element. 
     To ensure a sufficient fixing between the reflection and/or display element  13  on the one hand and the support element  16  (and the holding element  16 ′) on the other hand, the reflection and/or display element  13  is pressed against the support element  16 , and the reflection and/or display element  16  is linked (or pressed) against the support element  16  at three different points using first, second, third, fourth, fifth and sixth surfaces. The first, second and third surfaces  17  are curved surfaces having a first radius, whereas the fourth, fifth and sixth surfaces  18  are flat or curved surfaces having a second radius, the second radius corresponding to at least twice the first radius. In the example represented in the figures, the first, second and third surfaces  17  are produced on the reflection and/or display element  13  and more specifically on its side which is oriented toward the support element  16 . In the example represented in the figures, the fourth, fifth and sixth surfaces  18  are produced on the support element  16  such that the fourth, fifth and sixth surfaces  18  are located opposite the first, second and third surfaces  17  (see  FIGS. 3, 4, 5 and 6 ). 
     To ensure a sufficient fixing of the reflection and/or display element  13  between the holding element  16 ′ and the holding element  16 ′, the holding element  16 ′ bears against the reflection and/or display element  13  at three different points using seventh, eighth, ninth, tenth, eleventh and twelfth surfaces. The seventh, eighth and ninth surfaces  19  are curved surfaces having a third radius, whereas the tenth, eleventh and twelfth surfaces  20  are flat or curved surfaces having a fourth radius, the fourth radius corresponding to at least twice the third radius. In the example represented in the figures, the seventh, eighth and ninth surfaces  19  are produced on the holding element  16 ′ and more specifically on its side which is oriented toward the reflection and/or display element  13 . In the example represented in the figures, the tenth, eleventh and twelfth surfaces  20  are produced on the reflection and/or display element  13  such that the tenth, eleventh and twelfth surfaces  20  are located opposite the seventh, eighth and ninth surfaces  19  (see  FIGS. 7, 8 and 9 ). 
     While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. It will be understood that changes and modifications may be made by those of ordinary skill within the scope of the following claims. In particular, the present invention covers further embodiments with any combination of features from different embodiments described above and below. Additionally, statements made herein characterizing the invention refer to an embodiment of the invention and not necessarily all embodiments. 
     The terms used in the claims should be construed to have the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article “a” or “the” in introducing an element should not be interpreted as being exclusive of a plurality of elements. Likewise, the recitation of “or” should be interpreted as being inclusive, such that the recitation of “A or B” is not exclusive of “A and B,” unless it is clear from the context or the foregoing description that only one of A and B is intended. Further, the recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise. Moreover, the recitation of “A, B and/or C” or “at least one of A, B or C” should be interpreted as including any singular entity from the listed elements, e.g., A, any subset from the listed elements, e.g., A and B, or the entire list of elements A, B and C. 
     LIST OF REFERENCE SYMBOLS 
     
         
           10  display device 
           11  projection module 
           12  optical path 
           13  reflection and/or display element 
           14  windshield 
           15  normal direction of gaze 
           16  support element 
           16 ′ holding element 
           17  location of the first, second and third surfaces 
           18  location of the fourth, fifth and sixth surfaces 
           19  location of the seventh, eighth and ninth surfaces 
           20  location of the tenth, eleventh and twelfth surfaces