Transcript LCD Projectors and Document Cameras Defined

LCD Projectors and
Document Cameras Defined
Or everything you wanted to know but
didn’t know who to ask . . .
Projectors- Two main types:
• Digital Light Processing (DLP)
– Reflect light again hundreds of tiny mirrors called
digital micro devices (DMD)
– Each mirror represents one pixel
• Liquid Crystal Display (LCD)
– Operates by shining light through transparent red,
green and blue LCD cells
– Typically brighter than DLP projectors with the
same lumens
Does Size Really Matter?
• Ultralights - used for traveling presentation
– Weigh under 3 lbs.
– Typically 1000 - 2500 lumens
• Room Projectors
– Weigh in at 8 - 25 lbs
– Brighter than ultralights, 2500 - 5000 lumens
• Fixed Projectors
– Most expensive
– Usually in Auditoriums
– Range from 1000 - 10,000 lumens
Resolving the Resolution Issue
• Each projector has its own “native” resolution
at which it works best
• For best projection - set the computer and the
projector at the same display setting
• the most popular today being the XGA 1024 x
768 sold in the 4:3 aspect ratio
Projector Resolution Options
Resolution
Description
SVGA
800 x 600
Great for those on a tight budget. They’re good for PowerPoint
presentations that include clip art or line drawing, black and white, showing
documents, etc. They are not good for presentations that require a lot of
detail or video.
XGA*
1,024 x 768
Most computers still output in native XGA, so matching an XGA projector
to your computer ensures you won't lose any detail. These are good
general purpose projectors.
SXGA
1,280 x 1,024
SXGA projectors are high resolution, and will be more expensive than
XGA. These are targeted for high end personal computer users.
SXGA+
1,400 x 1,050
SXGA+ projectors are becoming more popular, and there are several
offerings available in both budget and high-end configurations. These are
very good for detailed photography and graphics.
UXGA
1,600 x 1,200
UXGA is for very high end high resolution workstation applications that
require exacting detail. These are expensive projectors that support a
broad range of computer equipment.
* The most popular projector resolution
Is what you see what you get?
• 4 Factors Determine Image Quality
– Contrast
– Color
– Brightness
– Illumination spread
Contrast and Color
• Difference between white & black
• Most important when projecting video
• Contrast ratio 250:1 minumum - 2000:1
great!
• More colors the better - especially for
video
• Should be able to display 16 million
colors or more
Brightness and Illumination
• Brightness indicated by ANSI Lumens
• Minimum 2500 Lumens for a classroom
• Illumination spread - is the image the
same brightness from top to bottom and
side to side
• 85% illumination uniformity or better
Let the Light Shine!
• Projector Lamps come in 3 main types:
– UHP - Ultra High Performance
– UHE - Ultra High Efficiency - most common
– Metal Halide
• Lamp life - 1000 - 4000 hours
• Lamp Cost - $300 - $600
– Include an extra lamp in the cost of the
projector
Conveniences (Extras)
• Wireless Projector
• Networked connections - remotely
controlled
• Component video inputs for higher
quality video
• Digital Keystone correction
• Wireless mouse control
• Dual computer input
Document Cameras
• Resolution
– Two categories - low resolution output (composite
and/or S-video) and those with high-resolution
output (1024x768 or higher).
• Refresh Rate
– 20 to 30 Frames per second
• Zoom Lens
• Features
• Size
Common Features
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Zoom 4 to 16x zoom
Pan
Auto Focus
Capture images - single or timed continuous
Playback images - view saved images
Freeze image - irregular shaped object
Brightness
Remote control
Bells and Whistles
• Effects - change from color to black and white
or negative
• Timer - time the image on the screen countdown
• Reverse Image
• Mirror Image
• Night view - lower the frame rate
• Download captured images
• Optional microscope connections
• Optional Interactive whiteboard connections
More Bells and Whistles
• Split Screen view - view both live and
captured image
• Picture in picture - view thumbnail of a
saved image with the “live” image in the
background
• Presenter view - shaded exterior with
clear view inside area
Why Should I Use One?
• How can they be used?
– Case Studies
– Using Document Cameras in the
Elementary Classroom
– Document Cameras in the classroom
– More Classroom Uses
– More Case Studies
Web Resources
• 6 Things You Need to Know about
Document Cameras
• LCD Projector Guide