JPH0846385A - Portable information processor - Google Patents

Abstract

PURPOSE:To simplify the connection structure between a display and a system unit while reducing the radiation noise accompanied with a high speed display. CONSTITUTION:In a lap top information processor comprising a system unit and a display connected through a hinge mechanism section, the system unit 4 is connected with the display 3 through an optical interface 16 and the housing of each unit is shielded individually. The optical interface 16 comprises a light emitting section disposed on the system unit side, a light receiving section disposed on the display side, and a tubular optical transmission path communicating them.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention reduces the noise radiated from an LCD device (liquid crystal display) operating at high frequency in a laptop type information processing device, and at the same time, it reduces the noise between the display device and the system device. The present invention relates to a portable information processing device having a simplified connection mechanism.

[0002]

2. Description of the Related Art In a laptop information processing device (personal computer, workstation, etc.), an LCD device is used as a display device in order to reduce its size and weight. Especially in recent years, with the progress of larger screens, higher definition, and colorization, LC
The drive frequency of D and the data transfer speed are high.

Due to such speeding up, the noise component radiated to the outside also has a high frequency band, and there is a limit in the conventional noise reduction method. For example, in order to reduce noise, the control interface of the LCD device is connected to the control board by a cable, in particular, by performing the waveform shaping on the interface to reduce the reflection waveform, and by matching the impedance between the board and the cable. The power supply ripple noise is reduced by reducing the harmonic noise and strengthening the connection to the ground (GND).

As an example of the above-mentioned lap top type information processing apparatus, for example, JP-A-5-19896, JP-A-5-150861, and JP-A-3-201.
597 publication etc. are mentioned.

[0005]

As described above, the LC
Since the drive frequency of the D device is high, the radiated noise component also has a wide band, and the signal is reflected and the waveform is distorted due to the line length of the interface cable connecting the LCD device and the system device. For this reason, it has become difficult to reduce noise by conventional impedance matching using a combination of L, C, and R. That is, as a means for impedance matching, a multilayer FPC (flexible printed wiring board) with a ground layer added is used for the shield of the interface cable, but the flexibility of the FPC deteriorates as the thickness of the FPC increases. There is a problem.

Further, in a laptop-type casing composed of a display device on which an LCD device or the like is mounted and a system device, a shielding method via a hinge mechanism portion for engaging the devices and a wiring route such as FPC are provided. Therefore, there is a problem that it is necessary to take measures for noise reduction in consideration of the above, and it takes considerable time and cost to develop the device.

It is an object of the present invention to provide a portable information processing apparatus which simplifies the connection mechanism between the display device and the system device while reducing the radiation noise accompanying the speeding up of the display device.

[0008]

In order to achieve the above object, according to the present invention, a housing of a system device having a CPU, a memory, an input / output device, etc. is connected to the system device via a hinge mechanism. In a portable information processing device including a display device housing, the system device housing and the display device housing are individually shielded, and an electrical signal is transmitted to the system device side of the hinge mechanism section. A light emitting unit for converting to an optical signal and outputting the light signal is provided, and a light receiving unit for converting the optical signal into an electric signal and outputting the electric signal is provided on the display device side of the hinge mechanism unit, and between the light emitting unit and the light receiving unit. A cylindrical light transmission path through which light propagates is provided integrally with the light receiving portion, and when the display device is rotated around the rotation axis of the hinge mechanism portion, the light transmission path is changed according to the rotation. It is designed to be movable on the surface of the light emitting part. It is characterized in that the.

[0009]

In order to remove the radiation noise, the housing of the display device on which the LCD device is mounted and the housing of the system device including the CPU, memory, input / output device, etc. are separately shielded,
In addition, the connection interface of the LCD device is set to optical transmission so that no current flows through the connection interface between the devices. Further, since the connection interface is electrically insulated by providing the optical transmission path in the hinge mechanism portion that engages each housing, disconnection of the interface cable does not occur and unnecessary radiation noise can be reduced. Further, since the mechanism is simplified, the opening / closing life of the mechanism case is extended.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 2 is a view showing the outer appearance of the portable information processing device of the present invention. In the figure, a portable information processing device 1 is composed of a display device 3 composed of an LCD 2 and a system device 4, and is connected by a hinge mechanism part 5 that engages between the display device 3 and the system device 4.

FIG. 1 is a functional block diagram of a portable information processing device. The system unit 4 includes a CPU 11 and a memory 1.
2. Input / output device 1 such as keyboard device and disk device
Equipped with 3. Further, the display adapter 14 and the optical interface 16 are connected, and the system device 4 is connected to the display device 3 via the optical interface 16. In this embodiment, since the optical interface is used as the connection interface between the devices, both can be electrically insulated. Further, the housing of the system device 4 and the housing of the display device 3 are individually shielded. Thereby, the radiation noise can be significantly reduced.

The optical interface 16 receives from the display adapter 14 electrical signals 15 (1 to n) such as a dot clock, horizontal synchronization, vertical synchronization, and RGB data necessary for display, and optical signals 17 (1 to n). To the display device 3. The optical signal 17 (1 to 1 transmitted to the display device 3
n) is converted into an electric signal in the conversion circuit 18 and then converted into LC
Input to D2. In addition, the conversion circuit 18 is the LCD 2
It may be configured to be built in.

The RGB data is transferred in synchronization with the dot clock, and the number of display elements is 1024 × 768 to 640 × 4.
For 80-dot LCDs, currently 20-50 ns
The transfer rate of is commonly used. In addition, the number of signal lines varies depending on the displayable color.
Approximately 50 are required for 6.7 million colors. The optical interface 16 of the present embodiment is composed of an interface that does not have a power line signal such as GND or Vcc.

The power supply to the display device 3 is performed as follows. As described above, the conversion circuit 18 is connected to the optical interface 16 in the display device 3, the power supply circuit 19 is connected to the conversion circuit 18, and the secondary battery 20 is connected to the power supply circuit 19. Then, power is supplied to the display device from the system device side.

The power supply circuit 19 includes an optical interface 16,
Means for accumulating electric power based on a constant output signal such as a dot clock input through the conversion circuit 18, obtaining a predetermined voltage, and means for charging and discharging the secondary battery 20 are provided. And the power supply to the LCD 2 is
It is performed from the secondary battery 20 through the power supply circuit 19. Since the electric power obtained from the optical interface 16 is relatively small, it is necessary to sufficiently charge the secondary battery 20 before use, but it can be sufficiently coped with when using a low power consumption device such as a reflective LCD. . In addition, since the backlight of the LCD consumes about 10 W at present, the capacity of the secondary battery is required to be about 20 Wh. There is a need to.

In the above-described embodiment, the power supply of the display device is supplied from the system device side, but the display device and the system device may have their own power supplies.

FIG. 3 is a view showing the hinge mechanism portion of the present invention. Here, as the hinge mechanism unit, for example, a rotation type one which is generally adopted in the laptop type at present is used. The hinge mechanism section 5 includes a rotation holding section 32,
Mechanism case 36, light guide band 31, light emitting section 33, light receiving section 3
4 and the shielding plate 32. 4 is a cross-sectional view taken along the line AA in FIG. 3, and in the state of FIG. 4, the mechanism case 3 having the LCD 2 built-in is centered on the rotation axis of the hinge mechanism portion.
It is a figure when 6 is rotated clockwise and it opens to the maximum.
FIG. 5 is a diagram of the minimum open / close state.

The optical transmission path will be described below with reference to FIGS. The optical interface 16 is composed of a plurality of light emitting portions 33 (1 to n) for converting an electric signal into an optical signal and a plurality of light receiving portions 34 (1 to n), and the plurality of light emitting portions 33 are system device main body portions 37. The plurality of light receiving portions 34 are provided in the mechanical case 36. Optical interface 1
The light transmission path 6 is configured by arranging the light emitting portions and the light receiving portions so as to face each other via the light guide band 31. Depending on the method of the hinge mechanism unit, the light emitting unit and the light receiving unit may be provided in the opposite manner to the embodiment.

The plurality of light guide bands 31 have a cylindrical shape and are housed in a mechanism case 36 together with the light receiving section 34. Also,
The light guide bands 31 are arranged at regular intervals so as to prevent optical interference between adjacent light guide bands. Light receiving section 34
Is the mechanical case 36 at a position corresponding to each signal of the light guide band 31.
It is fixed on. The light emitting portion 33 is provided inside the housing of the system device main body portion 37, and is provided while maintaining a constant gap from the circumferential surface of the hinge mechanism portion 5. The slit 38 provided in the light guide band 31 moves on the circumference of the hinge mechanism portion 5 by the opening / closing operation of the display device. 4 and 5, the light from the light emitting unit 33 reaches the light receiving unit 34 through the slit 38.

Furthermore, the surface of the light guide band 31 is coated so that light does not enter from the outside, and as shown in FIGS. A shielding plate 35 is provided to prevent light from entering the gap. The pitch of the light guide strips 31 is about 2 mm, and the gap between the light emitting section 34 and the light guide strips 31 is 1 mm to 2 mm.
set to mm. Further, by providing the light guide band 31 with a deflection characteristic, it is possible to improve the positional accuracy of the light guide band 31 and the light receiving section 34 and to cope with miniaturization of the hinge mechanism section.

[0021]

As described above, according to the present invention, in a laptop type information processing apparatus comprising a display device having an LCD device mounted thereon and a system device, the casing of each device is shielded, and Since the hinge mechanism that engages between devices is composed of an optical transmission line, radiation noise can be significantly reduced, disconnection of the interface cable can be prevented, and the opening and closing life of the mechanism case is long. Become.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a portable information processing device.

FIG. 2 is a diagram showing an appearance of a portable information processing device of the present invention.

FIG. 3 is a diagram showing a hinge mechanism portion of the present invention.

FIG. 4 is a cross-sectional view of a hinge mechanism portion in a maximum opened / closed state.

FIG. 5 is a cross-sectional view of a hinge mechanism portion, showing a minimum open / close state.

[Explanation of symbols]

 1 Portable Information Processing Device 2 LCD 3 Display Device 4 System Device 5 Hinge Mechanism Section 11 CPU 12 Memory 13 Input / Output Device 14 Display Adapter 15 Electrical Signal 16 Optical Interface 17 Optical Signal 18 Conversion Circuit 19 Power Supply Circuit 20 Secondary Battery

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location H04B 10/10 10/22 (72) Inventor Toshiyuki Ohara 810 Shimoimaizumi, Ebina City, Kanagawa Stock Company Hitachi Office Systems Division

Claims (1)

[Claims] 1. A portable information processing apparatus comprising: a housing of a system device having a CPU, a memory, an input / output device, etc .; and a housing of a display device connected to the system device via a hinge mechanism section. The housing of the system device and the housing of the display device are individually shielded, and a light emitting unit for converting an electric signal into an optical signal and outputting the optical signal is provided on the system device side of the hinge mechanism unit. A light receiving unit that converts an optical signal into an electric signal and outputs the light signal is provided on the display unit side of the mechanism unit, and a cylindrical optical transmission path through which light propagates is provided between the light emitting unit and the light receiving unit. It is provided integrally, and when the display device is rotated about the rotation axis of the hinge mechanism unit, the optical transmission path is configured to move on the surface of the light emitting unit according to the rotation. Portable information processing device.