Light pen - input and output devices, Computer Graphics

Assignment Help:

Light Pen - input and output devices

It is a pointing device. This has a light sensitive tip that is excited while the light is emitted and an illuminated point upon the display comes in its field of view. Different type of devices that have connected hardware to track the device and find out x and y values, the light pen requires software support as several kind of tracking program. Pointing operations are simply programmed for light pens.

2263_Light Pen - input and output devices.png

Figure: Light Pen Application

Figure in above shows two typical applications of a light pen. This has a light sensitive tip and also a photocell mounted in a pen-like case. Whether the light pen is pointed at an object on the screen this generates information from that the item can be identified through the program.

While the light pen senses an illuminated phosphor, this interrupts the display interpreting the processors of the file display. The instruction register of processor tells that instruction in the display file was being executed. Through identifying the instruction liable for the illuminated point that the machine can discover that object the pen is pointing to.

A light-pen is an event driven device. The processor that has to wait until it comes across an illuminated point on the display to acquire any information. The keyboard is the other typical illustration of an event driven device. Such processor has to wait for a key to be pressed before this can find out what the user needs to input.


Related Discussions:- Light pen - input and output devices

Objectives-visible-surface detection, After going through this section, you...

After going through this section, you should be capable to: know the meaning of Visible-surface detection; distinguish among image-space and object-space approach for vi

Important points about the diffuse reflection, Important Points About the D...

Important Points About the Diffuse Reflection An extremely rough surface appears uniformly bright from each viewing direction Q the intensity of reflected light is identical i

Explain the merits and demerits of plasma panel display, Explain the merits...

Explain the merits and demerits of Plasma panel display. Advantages: Refreshing is not needed. Produce a very steady image free of Flicker. Less bulky than a CRT.

What is computer-aided design, What is CAD Drawings created with Comput...

What is CAD Drawings created with Computer-Aided Design (CAD) tools, which were introduced in  the 1960s, represented tremendous productivity gains over paper drawings, such as

What is a blobby object, What is a Blobby object?  Some objects do not ...

What is a Blobby object?  Some objects do not handle a fixed shape, but change their surface characteristics in sure motions or when in proximity to other objects. That is call

Advantage and disadvantage of plasma panel-graphics hardware, Advantage and...

Advantage and Disadvantage of Plasma panel - Graphics Hardware Advantage 1. Slim design as Wall mountable 2. Larger than LCD screens Disadvantage

Forensics-applications for computer animation, Forensics: Accidents occur ...

Forensics: Accidents occur every minute. Very frequently, there are no witnesses except for the individuals concerned in the accident or worse yet, there are no surviving witnesse

Define the term -monitoring, Define the term -Monitoring Chemical and n...

Define the term -Monitoring Chemical and nuclear plants (monitoring key parameters), hospitals (monitoring patient's vital signs), burglar alarms (monitoring for intruders) etc

Introduction to computer graphics, Introduction To Computer Graphics ...

Introduction To Computer Graphics Early man employed drawings to communicate even before he learnt to communicate, write or count. Incidentally, these earliest hierogly

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd