EP0604216A2 - Dispositif d'affichage à cristaux liquides - Google Patents

Dispositif d'affichage à cristaux liquides Download PDF

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Publication number
EP0604216A2
EP0604216A2 EP93310424A EP93310424A EP0604216A2 EP 0604216 A2 EP0604216 A2 EP 0604216A2 EP 93310424 A EP93310424 A EP 93310424A EP 93310424 A EP93310424 A EP 93310424A EP 0604216 A2 EP0604216 A2 EP 0604216A2
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EP
European Patent Office
Prior art keywords
liquid crystal
crystal display
main body
display device
image
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP93310424A
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German (de)
English (en)
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EP0604216A3 (en
EP0604216B1 (fr
Inventor
Chikahiko Murata
Katsuya Mizukata
Yukihiro Nakahara
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Sharp Corp
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Sharp Corp
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Publication of EP0604216A2 publication Critical patent/EP0604216A2/fr
Publication of EP0604216A3 publication Critical patent/EP0604216A3/en
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Publication of EP0604216B1 publication Critical patent/EP0604216B1/fr
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    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
    • G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
    • G09F9/30—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements
    • G09F9/35—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements being liquid crystals

Definitions

  • the present invention relates to a liquid crystal display device used preferably as a display part of various apparatuses.
  • the liquid crystal display device can be formed in a smaller depth regardless of the display screen size as compared with the conventional display device using a cathode-ray tube. Additionally the liquid crystal display device is light in weight and small in power consumption. In spite of these excellent benefits, since liquid crystal molecules have a specific orientation, a viewing angle region where a favorable display image is observable is extremely limited.
  • the orientation processing of the substrate is done by rubbing method which enables to mass-produce the display element, in order to obtain an excellent display contrast, and a material possessing chirality of TN orientation complementary to a vector (groove direction) of a microgroove structure formed on the substrate surface by orientation processing is used as a liquid crystal material to be sealed between substrates.
  • Liquid crystal molecules are twisted in 90 degrees between two glass substrates of a TN type liquid crystal display device.
  • Microgrooves are formed on a surface of each substrate on the liquid crystal side in a certain direction, which is at right angles to each other direction of the microgrooves of each substrate surface.
  • the microgrooves are usually formed by application of rubbing treatment on a surface of a resin film formed on each substrate.
  • a liquid crystal material which is prepared by mixing liquid crystal molecules with a material for giving chirality is disposed between such substrates.
  • the liquid crystal molecules of the liquid crystal material arranged in the microgrooves have a character that they incline to the substrate face. Therefore, that material is employed as a material for giving chirality, which can compensate for insufficiency of twisting of the liquid crystal molecules of the twisted nematic liquid crystal in 90 degrees by twisting thereof through the directions of the microgrooves.
  • the orientation direction of liquid crystal molecules depends on the rubbing direction of the substrate surface, and the chirality is determined by the liquid crystal material.
  • the viewing angle region where a favorable display contrast is obtainable is limited, and in other viewing angle, especially when the viewing angle is set on the opposite side of the favorable viewing angle, the visible range is virtually too narrow to observe.
  • a solution for expanding the viewing angle region is to improve the liquid crystal material and orientation technology, but at the present no one has succeeded in development of the device where a favorable display image is observable from any viewing direction, such as the cathode ray tube.
  • a favorable display image is observable from any viewing direction, such as the cathode ray tube.
  • it is indispensable to match the favorable viewing angle region with the viewing angle direction of the highest frequency of observation.
  • the panel in a liquid crystal display device for car-mount application, the panel is properly used in correspondence to a viewing angle which is determined by an observation point and a position of device installation. That is, the panel to be used for installation in the region around a central console which is located below a driver's eye level is reverse in viewing angle to that to be used for suspending from a ceiling above the eye level.
  • Fig. 1 is an illustration for showing a definition of the viewing range.
  • a panel of six o'clock viewing angel means a panel where a preferable display can be observed in a direction of six o'clock.
  • a panel of twelve o'clock viewing angle means a panel where a preferable display can be observed in direction of twelve o'clock.
  • the liquid crystal display device of the invention comprises a main body of the device, positioning means of the main body, and posture holding means of the main body.
  • the main body of the device comprises liquid crystal display means having plural signal electrodes and plural scanning electrodes intersecting the signal electrodes, and driving means for driving the liquid crystal display means.
  • the driving means is designed to drive the liquid crystal display means so as to form a first display image on the basis of the video signal on the liquid crystal display means, and also to form a second display image rotating about 180 degrees the first display image from a specified point in the first display means.
  • the driving means comprises, for example, a signal electrode drive circuit for scanning plural signal electrodes, a scanning electrode drive circuit for scanning plural scanning electrodes, and an inverting control circuit for inverting the scanning direction of the signal electrode drive circuit and scanning electrode drive circuit.
  • the positioning means is constituted so as to selectively fix the main body between a first position in which the viewing angle for observing a display image of the liquid crystal display means from a predetermined observation point is included in an observable viewing angle region on the basis of the liquid crystal orientation of the liquid crystal display means at a predetermined first posture, and a second position in which the viewing angle for observing the display image from the observation point is included in an observable viewing angle region of the liquid crystal display means at a second posture where the liquid crystal display means at the first posture is rotated by about 180 degrees about the normal direction of the display screen.
  • the posture holding means is supported by the positioning means, and is constituted so as to hold the main body of the device in both first posture and second posture.
  • the viewing angle for observing the liquid crystal display means from the observation point is included in the observable viewing angle region, so that a favorable image may be observed.
  • the viewing angle for recognizing the display image on the liquid crystal display means from the observation point is included in the viewing angle region where a favorable display image is observable by fixing the main body at the second position by the positioning means, and holding the main body in the second posture rotating about 180 degrees from the first position by the posture holding means.
  • the second display image can be favorably recognized in the same direction as the first display image.
  • the positioning means comprises: a bar-shaped post member, means for supporting the post member by setting up in a vertical direction on a plane of installation such as a floor and a ceiling, being disposed at one end of the post member, and means for connecting other end of the post member and the main body.
  • the connecting means comprises: a dovetail tenon disposed on one side of either the other end of the post member or the main body of the device, and a connection member possessing a dovetail groove in which the dovetail tenon is fitted, being disposed on the other side.
  • the connecting means is composed of: a screw hole formed on either one of the other end of the post member and the main body of the device, and a bolt to be screwed in the screw hole provided at the other of the other end of the post member and the main body.
  • a protrusion is formed on either the dovetail tenon or the connection member, and a recess in which the protrusion is fitted is formed on the other thereof.
  • the connecting means functions as the posture holding means by selectively connecting a side of the main body to be on an upper side of an image displayed on the liquid crystal display means or a side of the main body to be on a lower side of the image with the other end of the post member.
  • the connecting means functions as the posture holding means by selectively connecting a side of the main body to be on a left side of an image displayed on the liquid crystal display means or a side of the main body to be on a right side of the image with the other end of the post member.
  • the post member is composed of two post members differing in length.
  • the post member is constituted so as to be flexibly expendable.
  • the positioning means comprises: a guide member, including a pair of guide posts disposed parallel to each other, wherein guide grooves are formed respectively in the mutually confronting surfaces of the guide posts, and a slide plate having an engagement piece to be engaged slidably with the guide groove, being disposed on the back side of the main body, wherein the guide member comprises position holding means disposed in the guide post, for holding the engagement piece and fixing the main body in the first or second position.
  • the posture holding means is composed of: a circular protruding portion being formed on the back side of the main body, and a hole in which the circular protruding portion is to be fitted formed in the slide plate, wherein either one of the circular protruding portion and the hole is provided with a detent protrusion and an operating part for projecting and retracting the detent protrusion and a detent hole in which the detent protrusion is to be fitted is formed at two positions differing in phase by 180 degrees from each other in the other of the circular protruding portion and the hole.
  • the main body of the device can be set either at the first or second position as desired, and it is designed so that the posture of the main body is changeable in two states differing in phase by 180 degrees, depending on the mode of the display image, so that a correct favorable image can be observed either at an upper or lower, or at a right or left position.
  • a single panel can be commonly used at different positions of use, that is, at positions differing in the viewing angle. Accordingly, the orientation processing of the liquid crystal display means is simplified and the working efficiency is notably improved, and, as a result, the manufacturing process and product control are substantially simplified, which contributes to reduction of cost. Moreover, among other excellent effects, the purchase is free of inconvenience of selecting in consideration of the place of installation.
  • Figs. 2 to 9 relate to an embodiment of application of the invention in a liquid crystal display device of a relatively large screen.
  • the device of this embodiment comprises a main body 1 and positioning means 2 for the main body 1.
  • the main body 1 comprises, as schematically shown in Fig. 3, a display panel 4 as liquid crystal display means provided in a main body outer shell 3, various control parts, operating parts (not shown), and others.
  • the display panel 4 is constituted by including a liquid crystal panel 34 of active matrix type TFT (thin film transistor) system. That is, in the liquid crystal panel 34, two glass substrates 51, 5b are disposed to be opposite to each other, a common electrode 6 composed of a transparent conductive film and an orientation film (not shown) are disposed on the surface of the substrate 5a on the panel front side which confronts the surface of the other substrate 5b, and a TFT switch matrix 7 and an orientation film (not shown) are provided on the confronting surface of the substrate 5b on the rear side, and a nematic liquid crystal layer 8 is sealed between the substrates 5a, 5b, more strictly between the orientation films so that the common electrode 6 and the TFT switch matrix 7 confront each other, and moreover polarizing plates are disposed on the outer surfaces of the substrates 5a, 5b. Furthermore, as required, backlight means 9 is disposed behind the rear side substrate 5b.
  • TFT thin film transistor
  • TFT switch matrix 7 As the main portion is schematically shown in Fig. 4, plural signal electrodes S and plural scanning electrodes G orthogonally crossing the signal electrodes S are disposed in matrix on the rear side substrate 5b, and a pixel electrode P and a TFT switch for connecting and disconnecting application of voltage to the pixel electrode P are disposed in the proximily of an intersection of the signal electrodes S and scanning electrodes G.
  • a semiconductor thin film 10 is used as a channel, and a signal electrode S as a source electrode and a pixel electrode G as a drain electrode are connected at both ends of the semiconductor thin film 10, and a gate electrode 11 extended from the scanning electrode G is opposite to the semiconductor thin film 10 through an insulation film 12.
  • Fig. 5 schematically shows an electric configuration of driving means 13
  • Fig. 6 schematically shows an arrangement of electrodes S, G, P of the TFT switch matrix 7 and the TFT switch T.
  • Fig. 7 shows a first display image 14a formed on a display panel 14 by the driving means 13 described below
  • Fig. 8 shows a second display image 14b rotating the first display image by 180 degrees from a given point (O) in the first display Image 14a. More specifically, the second display image 14b shown in Fig. 8 is obtained by rotating 180 degrees from the center point (O) of the first display image 14a, and the images are symmetrical vertically about the lateral center line L1 of the screen.
  • the TFT liquid crystal panel 34 is structured as shown in Fig. 4, and the pixel electrodes P are arranged as shown in Fig. 6.
  • This TFT liquid crystal panel 34 comprises, as shown in Fig. 6, plural parallel signal electrodes S1-S n (hereinafter called source bus lines), plural parallel scanning electrodes G1-G m (hereinafter called gate bus lines) which are orthogonal therewith, and matrix plural pixel electrodes P11-P mn connected through driving switching elements T11-T mn (TFT).
  • the driving means 13 comprises a video signal processing circuit 31 processing a complex video signal externally outputted, a source driver 32 controlling source bus lines S1-S n , a gate driver 33 controlling gate bus lines G1-G m , and an inversion control circuit 35 controlling the scanning sequence of the gate bus lines G1-G m and the inversion of the sequence of video signal application to the source bus lines S1-S n .
  • the video signal processing circuit 31 comprises a processing circuit 36 and a control circuit 37.
  • the processing circuit 36 separates video signals and synchronizing signals (a horizontal synchronizing signal and a vertical synchronizing signal) from complex video signals.
  • the video signal is transmitted to the source driver 32 and the synchronizing signal to the control circuit 37.
  • the control circuit 37 generates various control signals for controlling the source driver 32 and gate driver 33 to output to the source driver 32 and gate driver 33.
  • the source driver 32 comprises a bidirectional shift register 38, a sample holding circuit 39 and an output buffer 40.
  • the bidirectional shift register 38 outputs a start pulse SPD transmitted from the control circuit 37 to the sample holding circuit 39, shifting successively in timing when a clock signal CLD transmitted from the control circuit 37 is inputted.
  • the sample holding circuit 39 samples and holds a video signal transmitted from the processing circuit 36 in timing of outputted pulse from the bidirectional shift register 38 and outputs the holded video signals all at once to the output buffer 40 in response to a control signal from the control circuit 37 at the point of the time when all the video signals corresponding to the source bus lines S1-S n have been holded.
  • the output buffer 40 outputs the transmitted video signals to each of source bus lines S1-S n .
  • the bidirectional shift register 38 comprises a forward shift register 41, a backward shift register 42, output change-over means 43 for outputting from either of two shift registers 41, 42, and input change-over means 44 for inputting to either of the two shift register 41, 42.
  • the forward shift register 41 is composed of n pieces of flip-flops CF1-CF n .
  • the clock signal CLD is transmitted to each CK input of the flip-flops CF1-CF n in common to all the flip-flops.
  • the start pulse SPD is inputted via the input change-over means 44 to a D input of the flip-flop CF1.
  • the backward shift register 42 is composed of n pieces of flip-flops CR1-CR n .
  • the clock signal CLD is transmitted to each CK input of the flip-flops CR1-CR n in common to all the flip-flops.
  • the start pulse SPD is inputted via the input change over means 44 to a D input of the flip-flop CR n .
  • the output change-over means 43 is composed of n pieces of switches E1-E n .
  • the switches E1-E n change connection from between a common contact C and a contact A to between the common contact C and a contact B or vice versa in response to a change-over signal L/R from the inversion control circuit 35.
  • the contact B is connected to the Q output of the flip-flop CR i
  • the contact C is connected to a sample holding circuit 39.
  • the input change-over means 44 is embodied by a switch.
  • the switch changes connection from between the common contact C and the contact A to between the common contact C and the contact B or vice versa in response to a change-over signal L/R.
  • the contact A is connected to a D input of the flip-flop CF1, the contact B to a D input of the flip-flop Crn, and the start pulse is given to the contact C.
  • the gate driver 33 comprises a bidirectional shift register 45, a level shifter 46 and an output buffer 47.
  • the bidirectional shift register 45 outputs a start pulse SPS transmitted from the control circuit 37 to the level shifter 46, shifting successively in timing when a clock signal CLS transmitted from the control circuit 37 is inputted.
  • the level shifter 46 increases a potential of an inputted pulse up to a given potential and outputs as a scanning signal to the output buffer 47.
  • the output buffer 47 outputs the transmitted scanning signal to each of the gate bus lines G1-G m .
  • the bidirectional shift register 45 comprises a forward shift register 48, a backward shift register 49, output change-over means 50, and input change-over means 51.
  • the output change-over means 50 changes over from outputting from the shift register 48 to that from the shift register 49 or vice versa.
  • the input change-over means 51 changes over from inputting to the shift register 48 to that to the shift register 49 or vice versa.
  • the forward shift register 48 is composed of m pieces of flip-flops HF1-HF m .
  • the clock signal CLS is transmitted to each CK input of the flip-flops HF1-HF m in common to all the flip-flops.
  • the start pulse SPS is inputted via the input change-over means 51 to a D input of the flip-flop HR m .
  • the backward shift register 49 is composed of m pieces of flip-flops HR1-HR m .
  • the clock signal CLD is transmitted to each CK input of the flip-flops HR1-HR m in common to all the flip-flops.
  • the start pulse SPD is inputted via the input change over means 51 to a D input of the flip-flop HR n .
  • the output change-over means 50 is composed of m pieces of switches J1-J m .
  • the switches J1-J m change connection from between a common contact C and the contact A to between the common contact C and the contact A or vice versa in response to a change-over signal L/R from the inversion control circuit 35.
  • the contact B is connected to the Q output of the flip-flop HR i
  • the contact C is connected to the level shifter 46.
  • the input change-over means 51 is embodied by a switch.
  • the switch changes connecting from between the contact C and the contact A to between the contact C and the contact B or vice versa in response to the change-over signal L/R.
  • the contact A is connected to a D input of the flip-flop HF1
  • the contact B is connected to a D input of the flip-flop HRm
  • the start pulse SPS is given to the contact C.
  • the inversion control circuit 35 comprises a switch 52.
  • a constant voltage VDD is applied to one terminal of the switch 52, and the other terminal of the switch 52 is connected via a resistance 53 to a ground potential.
  • the potential of the other terminal of the switch 52 is outputted as a change-over signal L/R.
  • the switch 52 may be an electrical or mechanical one.
  • the voltage applied to the TFT is applied to the pixel electrode, and the light is controlled by driving the liquid crystal by the potential difference thereof from the voltage applied to the confronting common electrode.
  • Scan inversion of signal electrodes and scanning electrodes is described below with reference to the pixel arrangement schematic diagram in Fig. 6.
  • the diagram relates to the active matrix type TFT system, one side installation of a source and a gate driver, and stripe arrangement, but the invention may be also applied in other liquid crystal driving systems, driver arrangements, and pixel arrangement systems.
  • the liquid crystal driving signal voltage given to the liquid crystal through pixel electrodes P11-P mn is applied in the sequence of P11 ⁇ P12 ... ⁇ P 1 ⁇ n-1 ⁇ P 1n ⁇ P21 ⁇ P22 ... ⁇ P 2 ⁇ n-1 ⁇ P 2n ... ⁇ P m ⁇ n-1 ⁇ P mn , depending on the timing of the video signal voltage applied from the source driver to the source bus lines S1-S n , and the scanning signal applied from the gate driver to the gate bus lines G1-G m .
  • the image is inverted vertically and laterally by inverting the scanning direction of the source driver and gate driver S n ⁇ S1, G m ⁇ G1 respectively, thereby applying the voltage in the sequence of P mn ⁇ P m ⁇ n-1 ... ⁇ P m2 ⁇ P m1 ⁇ P m-1 ⁇ n ... ⁇ P m-1 ⁇ 2 ⁇ P m-1 ⁇ 1 ... P12 ⁇ P11.
  • a change-over signal L/R is changed to be in the high level state by turning on the switch 52 of an inversion control circuit 35 the switches 44, E1-E n are switched to the contact A side.
  • the start pulse SPD is inputted into flip flop CF1 consisting the forward shift register 41.
  • the clock signal CLD is inputted.
  • the start pulse is latched, outputted as Q output, and outputted to the sample holding circuit 39 through the switch E1.
  • Start pulses SPD are outputted sequentially from flip flop CF2-CF n to the sample holding circuit 39 at an interval of a one pulse of the clock signal CLD.
  • the switches 51, J1-J m are switched to the contact A by a high level change-over signal L/R.
  • the start pulse SPS is inputted to flip-flop HF1 constituting the forward shift register 48.
  • the start pulse SPS is latched, outputted as Q output, and outputted to the level shifter 46 via the switch J1.
  • Start pulses SPS are outputted sequentially from the flip-flop HF2-HF m to the level shifter 46 at the interval of a one pulse of the clock signal CLS.
  • a pulse corresponding to one horizontal period (horizontal period pulse) is applied from the gate driver 33 to the gate bus line G1
  • the video signal voltage applied from the source bus line S1 to S n is sequentially written into the pixel electrodes of the first line depending on the potential difference from the common electrode voltage, and in the next horizontal period, as a horizontal period pulse is applied to the gate bus line G2, the TFT of the second line is turned on, while the video signal voltage applied from the source bus lines S1 to S n in this period is written into the pixel electrodes of the second line.
  • the change-over signal L/R is changed to be in the low level state by turning off the switch 52 of the inversion control circuit further, each of the switches 44, E1-E n is switched to the contact B side.
  • the start pulse SPD is inputted into the flip-flop CR n constituting a backward shift register 42.
  • the start pulse SPD is latched, outputted as Q output and outputted via the switch E n to the sample holding circuit 39.
  • the start pulses SPD are outputted sequentially from the flip-flops CR n-1 -CR1 to the sample holding circuit 39 at a time interval of a one pulse of the clock signal CLD.
  • the switches 51, J1-J n are switched to be on the contact B side by the change-over signal L/R of low level.
  • the start pulse SPS is inputted to the flip-flop HR m constituting a backward shift register 49.
  • the clock signal CLS is inputted, thereby the start pulse SPS is latched, outputted as Q output, and outputted to the level shifter 46 via the switch J m .
  • the start pulses SPS are outputted sequentially from the flip-flops HR m-1 -HR1 at a time interval of a one pulse of the start pulse SPD is latched, outputted as Q output, and outputted to the clock signal CLS.
  • a pulse corresponding to one horizontal period (horizontal period pulse) is applied from the gate driver 33 to the gate bus line G m
  • the video signal voltage applied from the source bus line S n to S1 is sequentially written into the pixel electrodes of the m th line depending on the potential difference from the common electrode voltage, and in the next horizontal period, as a horizontal period pulse is applied to the gate bus line G m-1 , the TFT of the m-1th line is turned on, while the video signal voltage applied from the source bus lines S n to S1 in this period is written into the pixel electrodes of the m-1th line.
  • a picture an image
  • the liquid crystal panel 34 which composes the display panel 4 in the above-mentioned composition has an orientation film formed on each of the glass substrates 5a, 5b and subjected to orientation processing as mentioned in the description of the related art, and the liquid crystal layer 8 is composed of a liquid crystal material possessing a complementary chirality to the vector of the microgroove structure formed on the surface of the orientation film by the orientation processing. Therefore, the arrangement direction of liquid crystal molecules of the liquid crystal layer 8 is defined by the orientation film formed on the substrates 5a, 5b, which limit the viewing angle region capable of obtaining a favorable display contrast.
  • Circular patterns E1, E2 shown in Fig. 2 schematically show the viewing angle regions. Supposing the viewing angle region capable of observing the display panel 4 favorably is limited in a range indicated by hatched area of the whole viewing field, the display panel 4 is set at an upper setting position Pb as a first position capable of observing at a viewing angle ⁇ b from observation point Pa, and the direction of the display panel 4 is set so that the viewing angle region A capable of observing favorably at this time may be in the lower half of the whole viewing field shown in pattern E1.
  • the display panel 4 when the display panel 4 is set in a lower setting position Pc as a second position corresponding to a viewing angle ⁇ c from a viewing point(a), at this lower setting position Pc, by rotating the display panel 4 by 180 degrees, the viewing angle region A2 shown in pattern E2 is reverse in direction to the viewing angle region A1 and is suited to observing the image favorably.
  • the device of the embodiment is composed on the basis of this point, and the main body 1 may be installed in either upper or lower position, and it is possible to observe in a viewing angle region capable of observing favorably at either position.
  • the positioning means 2 is constituted by Including first and second connection members 15a, 15b mounted on the upper and lower sides of the main body outer shell 3, and first and second post members 16a, 16b differing in length.
  • These post members 16a, 16b are selectively used depending on the mounting position of the main body 1, and the dimensions thereof are set so that the longer first post 16a may support the device main body 1 at the upper setting position Pb, and the shorter second post member 16b, at the lower setting position Pc.
  • These post members 16a, 16b are formed out of solid materials or tubular materials having a square or circular section with a sufficient strength for supporting the weight of the main body 1, and are fixed on a floor or the like in standing position with proper support means 13.
  • first and second connection members 15a, 15b are individually formed in block pieces, and fixed to the middle region of the upper and lower sides of the main body outer shell 3, or integrally formed in the middle of the upper and lower sides of the main body outer shell 3, being constituted to have additionally the function of posture holding means in this embodiment as mentioned below.
  • Connecting means for connecting the post member 16a or 16b and the connection member 15a or 15b is formed on the upper ends of the first and second post members 16a, 16b and the ends of the first and second connection members 15a, 15b to be confrontingly connected therewith.
  • dovetail grooves 17a, 17b are provided on the ends of the first and second connection members 15a, 15b, as shown in Fig. 9, and dovetail tenons 18a, 18b to be fitted with the dovetail grooves 17a, 17b are formed on the upper ends of the first and second Post members 16a, 16b, and a locking protrusion 59 and a stopping recess 60 to be engaged with each other in the completely fitted state of the both are formed in the dovetail groove 17a or 17b and in the dovetail tenon 18a or 18b.
  • connection means is not limited to such constitution alone, but other stopping structures and various forms such as screw tightening structure using screw hole in one side and a bolt in the other side may be realized.
  • the main body 1 can be installed at either upper setting position Pb or lower setting position Pc. That is, when installed on the upper setting position Pb, the longer first post member 16a is fixed in standing position on the floor beneath the upper setting position Pb, and by engaging the dovetail 18a of the first post member 16a with the dovetail groove 17a of the first connection member 15a, the device main body 1 can be fixed and supported at the upper setting position Pb.
  • the viewing angle ⁇ b for observing the display image of the display panel 4 upward from the observation point Pa is at a height of a position included in the observable viewing angle region A1 on the basis of the liquid crystal orientation of the display panel 4.
  • the driving means 13 it is set so that the first display image 14a which is an erected image shown in Fig. 7 may be always formed on the display panel 4.
  • the second shorter post member 16b When installed at the lower setting position Pc, the second shorter post member 16b is fixed in the standing position on the floor, and the main body 1 is turned upside down, and by engaging the dovetail tenon 18b of the second post member 16b with the dovetail groove 17b of the second connection member 15b, the main body 1 can be fixed and supported at the lower setting position Pc in the state that the main body 1 installed at the upper setting position Pb is turned upside down, that is, in the posture that the main body 1 is rotated by 180 degrees.
  • the viewing angle ⁇ c for observing the display image of the display panel 4 downward from the observation point Pa is at a height of a position included in the observable viewing angle region A2 of the display panel 4 being inverted.
  • the second display image 14b is an inverted image of the first display image 14a, it can be observed as an erected image by forming an inverted image of the second display image 14b on the inverted display panel 4.
  • the main body 1 can be maintained, for example, in the first posture capable of observing the first display image 14a in the erected state thereof and in the second posture rotating 180 degrees from the first posture, so that the connection members 15a, 15b are also provided with the function of the posture holding means.
  • the main body 1 can be disposed at either of the setting positions Pb, Pc as desired.
  • the post members 16a, 16b may be also mounted on the ceiling, instead of the floor, and the main body 1 may be supported in suspended state.
  • the post members may be composed to be flexibly expandable.
  • Fig. 10 schematically shows the essential portion of other embodiment of the invention, and in this diagram, as the positioning means 2, a guide member 9 install in a standing state on a floor is provided, and the main body outer shell 3 is elevatably supported by the guide member 19.
  • the guide member 19 is composed of a pair of guide posts 20a, 20b which rise from the floor parallel to each other in a standing state and have a height capable of supporting the main body 1 at the upper setting position (2).
  • Guide grooves 21a, 21b are formed on the sides of the guide posts 20a, 20b confronting each other.
  • a slide plate 22 is disposed on the rear side of the main body outer shell 3, engaging pieces 23a, 23b to be slidably and elevatably engaged with the guide grooves 21a, 21b are projected on the rear side of the slide plate 22, and proper position holding means 23a, 24b are provided at positions corresponding to the upper setting position Pb and lower setting position Pc of the guide grooves 21a, 21b in order to hold the engaging pieces 23a, 23b at the positions.
  • Position holding means 24a and 24b have the same structure. As shown in Fig. 11, the position holding means 24a is disposed on the upper setting position Pb of the guide posts 20a and 20b and the position holding means 24b on the lower setting position C thereof. As an example, the position holding means 24a on a guide post 20a is explained.
  • a recess 81 is formed for disposing the position holding means 24a in guide post 20a.
  • a hole 82 is formed in the lower side of the recess 81.
  • the position holding means 24a is composed of rectangular parallelpiped portion 83, which is set and sunk in the recess 81, a protruding portion 84 formed in a surface 83a of the portion 83 and an engagement claw 85 formed on the surface 83a of the portion 83.
  • the position holding means 24a is attached to the upper portion of the recess 81 in angularly disposable condition around the axis 86 formed on the protruding portion 84.
  • the spring 87 is interposed between the surface 83a of the portion 83 and a bottom 81a of the recess 81.
  • the spring 87 is selected so that the outside surface 83b of the portion 83 and the outside surface 88 of the guide post 20a are in parallel in the natural length of the spring 87.
  • the end portion of the engagement claw 85 is not projected from the hole 82, the recess 90 into which the engagement claw 85 is inserted is formed on engagement piece 23a.
  • the protrusion 91 which is projected downward is formed on the upper side of the recess 90.
  • the position holding means 24a is angular-displaced around the axis 86, the engagement claw 85 is set in the recess 90, the end portion of the engagement claw 85 is hooked on the protrusion 91.
  • the spring 87 is contracted. Therefore, the engagement claw 85 and the protrusion 91 are engaged firmly by the elastic force of the spring 87.
  • the main body 1 is fixed.
  • the release operation of the engagement is as follows. That is, the engagement between the engagement claw 85 and the protrusion 91 is released when the engagement piece 23a is displaced upwardly in a vertical direction.
  • the position holding means 24a is angular-displaced by the elastic force of the spring 87, and returns to the original condition as shown in Fig. 12(1).
  • positioning means 2 by elevating the main body 1 along the guide member 19 and manipulating the upper position holding means 24a, the main body 1 can be fixed and supported at the upper setting position Pb, and by lowering the main body 1 along the guide member 19 and manipulating the lower position holding means 24b, the device main body 1 can be fixed and held at the lower setting position Pc.
  • the posture holding means is composed separately from the positioning means 2. That is, the posture holding means 25 is provided with a circular protruding portion 26 projecting in the middle of the rear side of the main body outer shell 3, and a fitting hole 27 of the nearly same diameter as that of the circular protruding portion 26 is formed in the slide plate 22, and the circular protruding portion 26 of the main body outer shell 3 is rotatably fitted in the fitting hole 27 in the slide plate 22.
  • a detent protrusion 28 and an operating part 29 for projecting/retracting the detent protrusion 28 are provided at a proper position of either the circular protruding portion 26 or fitting hole 27, and detent holes 30a, 30b are formed at two positions differing in phase by 180 degrees from each other in the other thereof.
  • Fig. 13 is a drawing for showing an enlarged plan view of the position holding means 25.
  • Fig. 14 is a sectional view seen from the section line A-A of Fig. 13.
  • the L-shaped detent member 93 is attached to the circular protrunding portion 26.
  • the detent member 93 is composed of the detent protrusion 28 and the operation part 29.
  • the detent protrusion 28 is inserted through the insertion hole 95 formed on the circular protruding portion 26, the end portion of the detent protrusion 28 is protruded out of the side of the circular protruding portion 26 due to the elastic force of the spring 94.
  • the operation part 29 is protruded outside from a long hole 92 communicating with the insertion hole 95.
  • the protruded detent protrusion 28 is inserted Into the detent hole 30a formed on the slide plate 22, whereby, the main body 1 is held.
  • the detent protrusion 28 is sunk in the circular protruding portion 26 by displacing the operation part 29 to the center 0 direction of the circular protruding portion 26. In this condition, the main body 1 can be rotated in relation to the slide plate 22. When the main body 1 is rotated in the above manner and the detent protrusion 28 is displaced to the position of the detent hole 30b, the end portion of the detent Protrusion 28 is inserted into the detent hole 30b due to the elastic force of the spring 94, the main body 1 is held in the inverted condition.
  • the posture holding means 25 thus composed, when the main body 1 is located at the upper setting position Pb, by putting the detent protrusion 28 into one detent hole 30a, the device main body 1 is held in standing position.
  • the engagement between the detent protrusion 28 and one detent hole 30a is released by manipulating the operating part 29, and the main body 1 is rotated 180 degrees around the circular protruding portion 26, and then the operating part 29 is manipulated again to put the detent protrusion 28 into the other stopping hole 30b, thereby the main body 1 is held in an inverted posture.
  • the main body 1 may be selected at either upper or lower position.
  • it may be also applied to a type capable of selecting the setting position right and left.
  • first and second display images are vertically symmetrical images, for example, as shown in Fig. 15 and Fig. 16, and the direction of right and left does not matter in particular.
  • the second display image 14b shown in Fig. 16 as an image rotated by 180 degrees about the image center point (O) is a laterally inverted image which is symmetrical about the lateral center line L2 of the screen.
  • a laterally displaceable type of the device may be easily composed in the other embodiment mentioned above.
  • the positioning means and posture holding means as comprising elements of the invention may be modified in various types aside from the foregoing embodiments.
  • the display image may be automatically rotated by 180 degrees by providing the driving means 13 with means for judging the top and bottom of the display image and interlocking the judging means with the posture holding means.
  • the judging means is constituted so that the first display image 14a is automatically formed on the display panel 4 when either one of the first and second connection members 15a, 15b is connected to the post member 16a or 16b, and the second display image 14b is formed when the other thereof is connected to the post member 16a or 16b.
  • the judging means is constituted so that the first display image 14a may be formed automatically when the detent protrusion 28 gets into either one of the detent holes 30a and 30b of the posture holding means 25, and that the second display image 14b is formed when getting into the other.
  • Fig. 17 is a drawing for showing the concrete structure of top and bottom judging means.
  • Switches 55 and 56 are attached to dovetail the tenons 17a and 17b, respectively. These switches 55 and 56 are conducted by connecting the dovetail grooves 18a and 18b to the dovetail tenons 17a and 17b.
  • the detecting circuit 67 switches the low level/high level of the change-over signal L/R on the basis whether or not the switches 55 and 56 are conducted.
  • the inversion control circuit 35 shown in Fig. 5 as mentioned above includes the switches 55 and 56, and the detecting circuit 57. Therefore, the image displayed at the time when the switch 55 is conducted and the image displayed at the time when the switch 56 is conducted are inverted mutually.
  • Fig. 18 is a schematic view showing a constitution example of the device in the case of utilizing the remote control system. The constitution will be described by way of example with reference to the embodiment shown in Fig. 18.
  • a switch 62 of an external remote control device 61 is pushed.
  • the external remote control device 62 transmits a predetermined signal.
  • the transmitted signal is received by a receiving portion 63 of the signal from the remote control device 62.
  • the received signal is transmitted to a control circuit 64.
  • the control circuit 64 drives a motor 65.
  • the motor 65 drives a gear 67 built in the engagement piece 23a toward a direction of an arrow 69.
  • the gear 67 is engaged with a tooth 68 formed in the groove 21a of the guide post 20a. Therefore, the main body 1 moves downward.
  • the control circuit 64 drives also a motor 66.
  • the motor 66 rotates a gear 70 built in the circular protruding portion 26 of the main body outer shell 3.
  • the gear 70 is engaged with a tooth formed on an inner side of the engagement hole 27 of the slide plate 22. Therefore, the main body 1 rotates about the circular protruding portion 26.
  • the engagement piece 23a moves downward along the guide post 20a and contacts with a switch 72 arranged at a lower end of the groove 21a of the guide post 20a. Thereby, the switch 72 is electrically conducted.
  • the control circuit 64 detects the conduction of the switch 72 and stops the motor 65. Thereby, the main body 1 stops at the lower position of the guide post 20a.
  • the gear 70 rotates along the tooth 71 and contacts with the switch 73. Thereby the switch 73 is electrically conducted.
  • the control circuit 64 detects the conduction of the switch 72 and stops the motor 66. Thereby the main body 1 is inverted.
  • control circuit 64 switches the level of the change-over signal L/R.
  • the image displayed on the liquid crystal panel 34 is inverted.
  • an observer can view a preferable image because the viewing angle in the case of the main body positioned in the upper position of the guide member 19 is the inverse of that in the case of the main body positioned in the lower position thereof.
  • the engagement piece 23a moves upward along the guide post 20a and contacts with a switch 76 arranged at an upper end of the groove 21a of the guide post 20a. Thereby the switch 76 is electrically conducted.
  • the control circuit 64 detects the conduction of the switch 76 and stops the motor 65. Thereby the main body 1 stops at the upper position of the guide post 20a. Further, the gear 70 rotates along the tooth 71 and contacts with a switch 77. Thereby the switch 77 is electrically conducted.
  • the switch 77 is arranged at a position confronting the switch 73 by 180 degrees.
  • the control circuit 64 detects the conduction of the switch 77 and stops the motor 66. Thereby the main body 1 is inverted. Further, in this condition, the control circuit 64 switches the level of the change-over signal L/R. Thereby an image displayed on the liquid crystal display panel 34 is inverted.

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  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Devices For Indicating Variable Information By Combining Individual Elements (AREA)
  • Liquid Crystal (AREA)
  • Liquid Crystal Display Device Control (AREA)
  • Transforming Electric Information Into Light Information (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
EP19930310424 1992-12-22 1993-12-22 Dispositif d'affichage à cristaux liquides Expired - Lifetime EP0604216B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP34244592A JPH06189233A (ja) 1992-12-22 1992-12-22 液晶表示装置
JP342445/92 1992-12-22

Publications (3)

Publication Number Publication Date
EP0604216A2 true EP0604216A2 (fr) 1994-06-29
EP0604216A3 EP0604216A3 (en) 1995-12-06
EP0604216B1 EP0604216B1 (fr) 1998-09-09

Family

ID=18353798

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19930310424 Expired - Lifetime EP0604216B1 (fr) 1992-12-22 1993-12-22 Dispositif d'affichage à cristaux liquides

Country Status (3)

Country Link
EP (1) EP0604216B1 (fr)
JP (1) JPH06189233A (fr)
DE (1) DE69320929T2 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4922478B2 (ja) * 2000-10-18 2012-04-25 ジョアリスター フラム エービー エル．エル．シー． 携帯用コンピュータ
JP2005169100A (ja) * 2003-11-20 2005-06-30 Aruze Corp 液晶表示装置および遊技機
JP5232886B2 (ja) * 2011-03-10 2013-07-10 シャープ株式会社 スタンド装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5674765A (en) * 1979-11-21 1981-06-20 Canon Inc Wrist watch type calculator
JPS5833179A (ja) * 1981-08-21 1983-02-26 Nec Corp 時計
GB2216703A (en) * 1988-03-22 1989-10-11 Nec Corp Receiver display
JPH05224207A (ja) * 1992-02-17 1993-09-03 Nec Corp 液晶表示素子

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5674765A (en) * 1979-11-21 1981-06-20 Canon Inc Wrist watch type calculator
JPS5833179A (ja) * 1981-08-21 1983-02-26 Nec Corp 時計
GB2216703A (en) * 1988-03-22 1989-10-11 Nec Corp Receiver display
JPH05224207A (ja) * 1992-02-17 1993-09-03 Nec Corp 液晶表示素子

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 005 no. 138 (P-078) ,2 September 1981 & JP-A-56 074765 (CANON INC) 20 June 1981, *
PATENT ABSTRACTS OF JAPAN vol. 007 no. 113 (P-197) ,18 May 1983 & JP-A-58 033179 (NIPPON DENKI KK) 26 February 1983, *
PATENT ABSTRACTS OF JAPAN vol. 017 no. 669 (P-1657) ,9 December 1993 & JP-A-05 224207 (NEC CORP) 3 September 1993, *

Also Published As

Publication number Publication date
DE69320929D1 (de) 1998-10-15
JPH06189233A (ja) 1994-07-08
DE69320929T2 (de) 1999-04-01
EP0604216A3 (en) 1995-12-06
EP0604216B1 (fr) 1998-09-09

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