×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Measuring Projector Light Output
3

Measuring Projector Light Output

Measuring Projector Light Output

(OP)
I'm looking for a way to measure the light output in lumens from a projection system. Any suggestions?

RE: Measuring Projector Light Output

Do you have access to a goniometer? This is the tool that will let you measure both light output and intensity at point location and total area, there are several, scan goniometers, image processor ganiometers, etc.

Reference this web site:

http://eetd.lbl.gov/btp/lsr/facilities/goniometer.html

Hope its helpfull.

RE: Measuring Projector Light Output

2
Hi Lylek,

Visit this link to Barco's website.  It has a useful explanation of measurement methods.  We use many LCD and CRT projectors in our applications and the practical value of CRT lumens is usually much lower than the manufacturer's spec.  This is because the brightness is expressed as a peak value; something rarely attainable in practise.

A pocket lightmeter and a flat matt white screen are all you need.  You can then easily convert illuminance readings to lumens values if you assume the screen has a lambertian gain.

http://www.barco.com/projection_systems/customer_services/advice.asp


Matt


RE: Measuring Projector Light Output

Hi Esanabri:

The goniometer measures ANGLEs, the gonio-photometer the
light vs. angle.

Lylek:
How much accuracy do you need ? Do you want to hust compare two projectors or do you need more detailed data e.g.
intensity vs. x-y coordinates ?

Do you need only one measurement or do you have to have
the instrumentation permanently attached?

<nbucska@pcperipherals.com>

RE: Measuring Projector Light Output

A simple Photometer will measure lumens per square centimeter being emmitted form the source.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources