Browse Prior Art Database

Grid-Less Pen Computer

IP.com Disclosure Number: IPCOM000113725D
Original Publication Date: 1994-Sep-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 45K

Publishing Venue

IBM

Related People

Miwa, I: AUTHOR [+2]

Abstract

Disclosed is a pen computer that is one of the components of notebook PC. The pen comprises a photo-sensor and a pressure-sensor. The photo-sensor detects light emission from the backlight of a LCD, and measures the pen's position when the pen is pointed on the LCD screen. The pressure sensor at the top of the pen senses whether the pen is pressed on the LCD screen. In response to sensing, an application software has only left half of the screen light up. If the pen is positioned on the left half, then the photo-sensor detects the light emission from the LCD screen. Accordingly, the application can recognize that the pen is positioned somewhere on the left half of the screen.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 88% of the total text.

Grid-Less Pen Computer

      Disclosed is a pen computer that is one of the components of
notebook PC.  The pen comprises a photo-sensor and a pressure-sensor.
The photo-sensor detects light emission from the backlight of a LCD,
and measures the pen's position when the pen is pointed on the LCD
screen.  The pressure sensor at the top of the pen senses whether the
pen is pressed on the LCD screen.  In response to sensing, an
application software has only left half of the screen light up.  If
the pen is positioned on the left half, then the photo-sensor detects
the light emission from the LCD screen.  Accordingly, the application
can recognize that the pen is positioned somewhere on the left half
of the screen.  To the contrary, if the pen is postioned on the right
half, then the photo-sensor doesn't detect the light emission, but
the application can also recognize that the pen is positioned on the
right half of the screen (Fig. 1).  Next step is to perform the same
step for the recognized half portion.  As a result, you can measure
the rough position of the pen in a short time period.  For example,
it takes 8/60 seconds to limit 40x30 dots area out of 640x480 dots
full screen size.

      To measure more precise position, the following step may be
operated.  Once 40x30 dots area was determined, the 40x30 dots area
is divided into 4 rows and 4 columns as depicted in Fig. 2.  Then
each row and column is flashed in order.  The out put signal from the
photo-s...