Digital Projection Projector HIGHlite 660 3D Series User Manual

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Reference Guide
THE DMD™
Depending on the voltage polarity applied, each mirror will either tilt \
to the left to produce a bright pixel or to the right for a dark pixel. \
When 
light is applied to the complete DMD™, only the light redirected from\
 a mirror tilting to the left is projected.
1Projection lens
2Incoming light from the lamp
3Mirror element tilted to the right
4Mirror element tilted to the left
5Reflected light, left tilt
6Light dump
7Reflected light, right tilt
The projector optically filters white light from the lamp into its 
constituent red, green and blue. Each color illuminates a separate DMD™\
 whose modulated output is then recombined with the other two to 
form the projected full color image.
1Lamp
2Optical filtering of light into red, green and blue
3Projection lens
4DMD™ devices
5Full color image displayed on screen
Notes
Light flow
1
2
3
4
5
6
7
white lightwhite light
blue  
light green
 
light red 
light
123
45
Filtering process
   
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Reference Guide
CHOOSING A LENS
Choosing A Lens
A number of lenses are available. Which lens you choose depends on the sc\
reen size, image aspect ratio, throw distance and light output.
The following table shows all available lenses in order of their throw ratios:
Throw ratiosThrow distance range
0.77 : 1 fixed lens1.3 - 2.5 m (4.3 - 8.2 ft)
1.16 : 1 fixed lens1.4 - 6.2 m (4.6 - 20.3 ft)
1.45 - 1.74 : 1 zoom lens1.8 - 9.3 m (5.9 - 30.5 ft)
1.74 - 2.17 : 1 zoom lens2.2 - 11.8 m (7.2 - 38.7 ft)
2.17 - 2.90 : 1 zoom lens2.7 - 15.4 m (8.9 - 50.5 ft)
2.90 - 4.34 : 1 zoom lens3.6 - 22.5 m (11.8 - 73.8 ft)
4.34 - 6.76 : 1 zoom lens5.5 - 35 m (18 - 115 ft)
To choose a lens, either calculate the throw ratio required, or use the lens charts provided at the end of this guide.
Notes
 For information about individual lens 
part numbers, see Appendix A at 
the end of this document.
   
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Reference Guide
CHOOSING A LENS
Basic calculation
Identify the required lens by calculating the throw ratio.
A throw ratio is the ratio of the throw distance to the screen width:
Throw distanceScreen width
Throw ratio =
1. Use the formula above to obtain the required throw ratio.
2. Match the throw ratio with a lens from the table below:
Throw ratiosThrow distance range
0.77 : 1 fixed lens1.3 - 2.5 m (4.3 - 8.2 ft)
1.16 : 1 fixed lens1.4 - 6.2 m (4.6 - 20.3 ft)
1.45 - 1.74 : 1 zoom lens1.8 - 9.3 m (5.9 - 30.5 ft)
1.74 - 2.17 : 1 zoom lens2.2 - 11.8 m (7.2 - 38.7 ft)
2.17 - 2.90 : 1 zoom lens2.7 - 15.4 m (8.9 - 50.5 ft)
2.90 - 4.34 : 1 zoom lens3.6 - 22.5 m (11.8 - 73.8 ft)
4.34 - 6.76 : 1 zoom lens5.5 - 35 m (18 - 115 ft)
3. Ensure the required throw distance is within the range covered by the le\
ns.
Notes
 
The basic calculation on this page 
does not take into consideration 
DMD™ and image size, which could 
affect the throw ratio. For a more 
complex and realistic calculation, 
see Full lens calculation  in this 
section.
  When calculating the throw ratio, be 
sure to use identical measurement 
units for both the throw distance and 
the screen width.
 For information about individual lens 
part numbers, see Appendix A at 
the end of this document.
12
1Screen width
2Throw distance
   
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Reference Guide
CHOOSING A LENS
Basic calculation example
1. Calculate the throw ratio using the formula.
Your screen is 4.5 m wide and you wish to place the projector 
approximately 11  m from the screen. The throw ratio will then be
  
11
4.5 = 2.44
2. Match the result with the lens table.
The lens matching a throw ratio of 2.44 is the 2.17 - 2.90 : 1 
zoom lens.
3. Check whether the lens covers the required throw distance. 
The range quoted for the 2.17 - 2.90 : 1 zoom lens is  2.7 - 15.4 
m. The required distance of 11 m is within the range.
Notes
  The basic calculation on this page 
does not take into consideration 
DMD™ and image size, which could 
affect the throw ratio. For a more 
complex and realistic calculation, 
see Full lens calculation  in this 
section.
  For information about individual lens 
part numbers, see Appendix A at 
the end of this document.
INFORMATION YOU NEED FOR THIS CALCULATION
• The throw ratio formula:
Throw distanceScreen width
Throw ratio =
• The lens table:
Throw ratios
Throw distance range
0.77 : 1 fixed lens 1.3 - 2.5 m (4.3 - 8.2 ft)
1.16 : 1 fixed lens 1.4 - 6.2 m (4.6 - 20.3 ft)
1.45 - 1.74 : 1 zoom lens 1.8 - 9.3 m (5.9 - 30.5 ft)
1.74 - 2.17 : 1 zoom lens 2.2 - 11.8 m (7.2 - 38.7 ft)
2.17 - 2.90 : 1 zoom lens 2.7 - 15.4 m (8.9 - 50.5 ft)
2.90 - 4.34 : 1 zoom lens 3.6 - 22.5 m (11.8 - 73.8 ft)
4.34 - 6.76 : 1 zoom lens 5.5 - 35 m (18 - 115 ft)
   
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Reference Guide
CHOOSING A LENS
Full lens calculation
Introducing TRC
The choice of lens will affect the image size and will address discrepancies between the 
DMD™ resolution and the source.
When an image fills the height of the DMD™ but not the width, it uses less than 100% of 
the DMD™ surface. A lens chosen using the basic formula may produce an image that is 
considerably smaller than the actual screen.
To compensate for loss of screen space in such situations, you need to in\
crease the throw 
ratio using a Throw Ratio Correction (TRC).
Example
Fig. 1 illustrates a 4:3 image within a 1080p DMD™.
When a 1080p projector is used for a 4:3 image, the image does not fill the width of the 
DMD™, creating a pillarboxing effect - blank spaces to the left and right.
Fig. 2 shows the same image projected on a 4:3 screen using a standard lens (\
chosen with 
the basic calculation).
The DMD™ accurately fills the width of the screen; however, the pillarboxing is now part of the 
projected image and is transferred to the screen.
The DMD™ does not fill the height of the screen, which has caused letterboxing - further 
blank spaces at the top and bottom of the screen.
The image is now surrounded by blank space, which can be removed if the \
throw ratio is 
increased.
Fig. 3 shows the image projected on the same screen with a lens chosen using\
 TRC.
The increased throw ratio has allowed the 4:3 image to fill the 4:3 screen seamlessly.
Notes
 TRC can only be applied if greater 
than 1. If TRC is 1 or less, disregard 
it and calculate the throw ratio using 
the basic formula.
Fig. 1
Fig. 2
Fig. 3
   
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CHOOSING A LENS
Calculating TRC
To calculate TRC, use the following formula:
DMD™ aspect ratioSource aspect ratio
TRC =
TRC table
Alternatively, you can save time by referencing the following table, which shows the \
TRC value for some popular image formats:
HIGHlite 660 3D 1080pHIGHlite 660 3D WUXGA
2.35:1 (Scope), 1920 x 817 pixelsTRC < 1, not usedTRC < 1, not used
1.85:1 (Flat), 1920 x 1037 pixelsTRC < 1, not usedTRC < 1, not used
1.78:1 (16:9), 1920 x 1080TRC = 1, not used (native resolution)TRC < 1, not used
1.66:1 (Vista), 1792 x 1080 pixelsTRC = 1.07TRC < 1, not used
1.6:1 (16:10), 1728 x 1080 pixelsTRC = 1.11TRC = 1, not used (native resolution)
1.33:1 (4:3), 1440 x 1080 pixelsTRC = 1.33TRC = 1.2
1.25:1 (5:4), 1350 x 1080 pixelsTRC = 1.42TRC = 1.28
Notes
 
TRC can only be applied if greater 
than 1. If TRC is 1 or less, disregard 
it and calculate the throw ratio using 
the basic formula.
   
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CHOOSING A LENS
Calculating the throw ratio with TRC
1. For TRC > 1, amend the basic throw ratio formula as follows:
Throw distance
Screen width  x TRC
Throw ratio =
2. Once a throw ratio is established, identify the matching lens from the t\
able:
Throw ratiosThrow distance range
0.77 : 1 fixed lens1.3 - 2.5 m (4.3 - 8.2 ft)
1.16 : 1 fixed lens1.4 - 6.2 m (4.6 - 20.3 ft)
1.45 - 1.74 : 1 zoom lens1.8 - 9.3 m (5.9 - 30.5 ft)
1.74 - 2.17 : 1 zoom lens2.2 - 11.8 m (7.2 - 38.7 ft)
2.17 - 2.90 : 1 zoom lens2.7 - 15.4 m (8.9 - 50.5 ft)
2.90 - 4.34 : 1 zoom lens3.6 - 22.5 m (11.8 - 73.8 ft)
4.34 - 6.76 : 1 zoom lens5.5 - 35 m (18 - 115 ft)
3. Ensure the required throw distance is within the range of the matching l\
ens.
Notes
 
TRC can only be applied if greater 
than 1. If TRC is 1 or less, disregard 
it and calculate the throw ratio using 
the basic formula.
   
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Reference Guide
CHOOSING A LENS
Full lens calculation example
Your screen is 4.5 m wide; you wish to place the projector 
approximately 11  m from the screen. You use a WUXGA 
projector; the source is 4:3.
1. Calculate TRC as follows:
1.6
1.33
TRC = = 1.2
2. Calculate the throw ratio:
11
4.5 x 1.2
Throw ratio = = 2.04
3. Find a match in the lens table.
The table shows that the matching lens is the 1.74 - 2.17 : 1 
zoom lens.
4. Check whether the lens covers the required throw distance.
The range quoted for the 1.74 - 2.17 : 1 zoom lens is 
2.2 - 11.8 m. The required distance of 11 m is within the 
range.
Notes
INFORMATION YOU NEED FOR THESE CALCULATIONS
• The TRC formula
• The TRC table (to use instead of the formula)
HIGHlite 660 3D WUXGA
2.35:1 (Scope) TRC not used
1.85:1 (Flat) TRC not used
1.78:1 (16:9) TRC not used
1.66:1 (Vista) TRC not used
1.6:1 (16:10) TRC not used (native resolution)
1.33:1 (4:3) TRC = 1.2
1.25:1 (5:4) TRC = 1.28
• The throw ratio formula
• The lens table:
Throw ratios Throw distance range
0.77 : 1 fixed lens 1.3 - 2.5 m (4.3 - 8.2 ft)
1.16 : 1 fixed lens 1.4 - 6.2 m (4.6 - 20.3 ft)
1.45 - 1.74 : 1 zoom lens 1.8 - 9.3 m (5.9 - 30.5 ft)
1.74 - 2.17 : 1 zoom lens 2.2 - 11.8 m (7.2 - 38.7 ft)
2.17 - 2.90 : 1 zoom lens 2.7 - 15.4 m (8.9 - 50.5 ft)
2.90 - 4.34 : 1 zoom lens 3.6 - 22.5 m (11.8 - 73.8 ft)
4.34 - 6.76 : 1 zoom lens 5.5 - 35 m (18 - 115 ft)
DMD™ aspect ratio
Source aspect ratioTRC =
Throw distance
Screen width x TRCThrow ratio =
   
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SCREEN REQUIREMENTS
Screen Requirements
Fitting the image to the DMD™
If the source image supplied to the projector is smaller than the DMD™ resolution, the image will not fill the DMD™. The following examples 
show how a number of common formats may be displayed, depending on your \
DMD™ resolution.
1080p images displayed full width
Notes
2.35:1(Scope) 
 =  817 pixels
full width = 1920 pixels
1.85:1 
 = 1037 pixels
16:9 = 1.78:1  
= 1080 pixels 
(native resolution)
   
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SCREEN REQUIREMENTS
1080p images displayed full heightNotes
4:3 = 1.33:1 = 1440 pixels
full height = 1080 pixels
1.66:1 (Vista) = 1792 pixels16:9 = 1.78:1 = 1920 pixels  
(native resolution)
16:10 = 1.6:1 = 1728 pixels
   
Digital Projection HIGHlite 660 3D Series 
Rev E Februar y 2015