Skip to page content |

Tiscali Quicklinks. Please visit our Accessibility Page for a list of the Access Keys you can use to find your way around the site, skip directly to the main navigation, to the page content, or to more links within reference.

Advertisement starts

Advertisement ends

Content Starts Here

light pen

encyclopaedia header
Encyclopaedia Search
Click a letter for the index
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Or search the encyclopaedia:
 
 
 
all results tagged with the © symbol denotes content that is relevant to the national curriculum

Light Pen


In computing, a device resembling an ordinary pen, used to indicate locations on a computer screen. With certain computer-aided design (CAD) programs, the light pen can be used to instruct the computer to change the shape, size, position, and colours of sections of a screen image.

The pen has a photoreceptor at its tip that emits signals when light from the screen passes beneath it. From the timing of this signal and a gridlike representation of the screen in the computer memory, a computer program can calculate the position of the light pen.

© Research Machines plc 2008. All rights reserved. Helicon Publishing is a division of Research Machines plc.


 
Back
 

Advertisement starts

Advertisement ends



bar code
concept keyboard
digital camera
digital recording
digitizer
document reader
function key
graphics tablet
input device
interactive whiteboard
joystick
keyboard (computing)
light pen
magnetic strip
magnetic-ink character recognition
mark sensing
microphone
mouse (computing)
optical character recognition
optical mark recognition
point-of-sale terminal
punched card
QWERTY
scanner (computing)
sensor
smart card
speech recognition
touch screen
trackball
TWAIN

Related Links

Dominican Republic Flag
Dominican Republic Flag The arms show a Bible open at the Gospel of St John, a Trinitarian symbol. The white cross symbolizes faith. The arms appear on national and state flags. Effective date: 14 September 1863. >>

Advertorial

AdvertorialFind out how to buy the things you've always wanted and sell the things you don't on ebay.

Advertisement starts

Advertisement ends

More Links Within This Section

-->
encylopaedia

Page Footer

print now Print now send to a friend Send to a friend related articles Related articles related products Related products

Check shares

Check shares
Look up latest prices
more...

Best Loans

Best Loans
Search for the best rate.
more...

Dating

Dating
Find the love of your life
more...

TV guide

TV Guide
What's on the box?
more...
| Advertise | Press | Work at Tiscali | Site Map | Service Status | Help | Contact Us
© Tiscali 2008
IT | NET

Access keys


You will need to use different key combinations in order to use access keys depending on your internet browser, find out which on our accessibility page.
  • (0) Navigate to Accessibility page.
  • (1) Navigate to Home page.
  • (2) Navigate to My email.
  • (3) Navigate to My Account.
  • (4) Navigate to Site Map page.
  • (5) Navigate to Contact us page.
  • (6) Navigate to Members channel.
  • (7) Navigate to Services channel.
  • (8) Navigate to News & Info channel.
  • (9) Navigate to Entertainment channel.
  • ([) Skip down to the Primary navigation block.
  • (]) Skip down to the more links within this section block.
  • (=) Bypass all navigation and jump to the content.