Active solid-state devices (e.g. – transistors – solid-state diode – Non-single crystal – or recrystallized – semiconductor... – Amorphous semiconductor material
Reexamination Certificate
2001-12-12
2004-06-08
Nelms, David (Department: 2818)
Active solid-state devices (e.g., transistors, solid-state diode
Non-single crystal, or recrystallized, semiconductor...
Amorphous semiconductor material
C257S059000, C257S053000
Reexamination Certificate
active
06747290
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an information device having a function for inputting information by using means such as a pen. In particular, the present invention relates to an information device in which pen input operations are performed on a screen of a display device. The present invention relates to an EL display device using EL elements as the display device, and further, relates to electronic devices, such as portable information devices, having the information device of the present invention.
Note that, in this specification, the term EL element denotes an EL element utilizing both light emission from singlet excitons (fluorescence) and light emission from triplet excitons (phosphorescence).
2. Description of the Related Art
The demand for pen input method portable information devices has risen in terms of miniaturization and operability. The pen input method is a method for the input of information by using a specialized pen or arbitrary pen, and by either contacting pen tip to a display screen, or bringing the pen tip close to the display screen.
Namely, input of information corresponding to positions indicated by the pen tip on the display screen is performed. The display screen also functions as a pen input screen. It is necessary to specify the positions indicated by the pen on the pen input screen with this pen input method, and methods such as a resistive film method and an optical method exist as means for the pen input.
The resistive film method is explained first.
FIG. 7
is a cross sectional diagram showing the structure of a resistive film pen input device. Note that a pen input device
7711
is formed overlapping with and on the upper portion of a display device
7708
. The display device
7708
has a display portion
7709
and a peripheral circuit
7710
.
A movable electrode
7701
and a fixed electrode
7702
sandwich dot spacers
7704
in the pen input device
7711
, and both are connected in parallel with a gap of approximately 100 to 300 &mgr;m by a lamination material
7703
. The movable electrode
7701
and the fixed electrode
7702
are formed by conductive materials having transparency so that images projected on the display portion
7709
of the display device
7708
can be seen through the pen input device
7711
. In general, an indium tin oxide (ITO) film is used as the conductive material having transparent properties.
The movable electrode
7701
touches the fixed electrode
7702
in a position indicated by the input pen
7704
on the pen input device
7711
with the resistive film method (input point A in FIG.
7
). At this time, in the method, the position of the input point A is read out as the ratio of resistances R
1
and R
2
from two position detection electrodes
7706
and
7707
.
Specifically, an example of performing position read out is shown in
FIG. 8. A
pressure is applied by an input pen
807
from a movable electrode
801
side and there is contact between the movable electrode
801
and a fixed electrode
802
at the input point A. A voltage is applied between two electrodes
803
and
804
of the movable electrode
801
here, and an electric potential gradient is generated within the movable electrode
801
. By measuring the electric potential V
A
of the input point A at this point, resistance values R
x1
and R
x2
from the electrode
803
and the electrode
804
to the input point A can be found. If the film quality of the movable electrode
801
is assumed to be uniform, then the resistance values R
x1
and R
x2
are proportional to the distances from the electrodes
803
and
804
to the input point A, respectively.
Similarly, a voltage is applied between two electrodes
805
and
806
of the fixed electrode
802
, and an electric potential gradient within the fixed electrode
802
is generated. By knowing the electric potential V
A
of the input point A at this point, resistance values R
y1
and R
y2
from the electrode
805
and the electrode
806
to the input point A can be found. If the film quality of the fixed electrode
802
is assumed to be uniform here, then the resistance values R
y1
and R
y2
are proportional to the distances from the electrodes
805
and
806
to the point A, respectively. The position of the input point A can thus be determined.
Note that the method of measuring the electric potential of the input point A for measuring the position of the input point A is not limited to the above structure, and various other methods can also be used.
An optical method pen input device is explained next. A schematic diagram of an upper surface of the optical method pen input device is shown in FIG.
9
A.
If a pen tip of an input pen
901
makes contact to an input portion
902
, the contact position is detected. The position detection operation is explained.
X-
1
light emitting diodes (hereafter referred to as LEDs)
2
1
to
2
x
are arranged in a right edge portion in the periphery of the input portion
902
, and x-
1
phototransistors (hereafter referred to as PTs)
3
1
to
3
x
are arranged in a left edge portion of the input portion
902
, opposite the LEDs
2
1
to
2
x
. The light emitting diodes and the phototransistors are embedded in a frame
4
.
Y-
1
LEDs
5
1
to
5
y
are arranged in a lower edge portion, and y-
1
PTs
6
1
to
6
y
are arranged in an upper edge portion, opposite the LEDs
5
1
to
5
y
. The LEDs and the PTs are embedded in the frame
4
.
The LEDs
2
1
to
2
x
and the PTs
3
1
to
3
x
form x-
1
horizontal direction touch input lines, and the LEDs
5
1
to
5
y
and the PTs
6
1
to
6
y
form y-
1
vertical direction touch input lines.
The term touch input lines refer to paths along which light emitted from the LEDs travels when input to the PTs between pairs of opposing LEDs and PTs.
Note that although PTs are used as the components having reference numerals
3
1
to
3
x
and
6
1
to
6
y
, there is no limitation associated with PTs, and other components can be freely used provided that they are photoelectric conversion elements that convert light into an electric signal.
In order to increase the directionality of light emitted from the LEDs
2
1
to
2
x
and
5
1
to
5
x
, and made incident on the PTs
3
1
to
3
x
and
6
1
to
6
x
, hole shaped slits
7
are formed in front of the frame
4
in which each of the elements is embedded.
FIG. 9B
is a cross sectional diagram along a line segment a—a of
FIG. 9A. A
display device
910
is formed in a portion below the pen input device. The display device
910
is structured by a display portion
911
and a peripheral circuit
912
. Differing from the resistive film method, it is possible to directly see images displayed in the display portion
911
.
FIG. 9A
is again referenced.
The emission of light and the receiving of light are performed one pair at a time from the edge for the pairs of opposing LEDs and PTs. This operation (hereafter referred to as scanning) is performed at the same time for the horizontal direction touch input lines and the vertical direction touch input lines in the pen input device having the above structure.
One point within the input portion
902
is indicated by the input pen
901
. The input point A within
FIG. 9A
is indicated. Light is cutoff between two touch lines
2
n
to
3
n
and
5
m
to
6
m
at this point, and the position A at which the input pen
901
contacts is recognized.
It is necessary to mechanically change the shape of the movable electrode as information is input with the resistive film method. The movable electrode thus fatigues with repeated shape change, and there is the possibility of it being broken. This becomes an endurance problem.
Further, even if damage does not reach actual breakage, the ITO film conductivity becomes non-uniform due to repeated deformation and in the case where minute cracks on the order of micrometers in size are formed during manufacturing process. Therefore, problems in the precision of input pen location detection develop.
In addition, the display device image is read out thro
Koyama Jun
Yamazaki Shunpei
Fish & Richardson P.C.
Nelms David
Nguyen Thinh T
Semiconductor Energy Laboratory Co,. Ltd.
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