Digital Projection Projector M-Vision 930 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 illumination module
3Mirror element tilted to the right
4Mirror element tilted to the left
5Reflected light, left tilt
6Light dump
7Reflected light, right tilt
The projector uses a color wheel to split white light from the lamp into\
 its constituent red, green and blue. The color wheel sends red, green 
and blue light sequentially to the DMD™. The modulated output of the DMD™ is synchronized with the color wheel to form the projected full 
color image.
1Lamp
2Color wheel
3DMD™ device
4Projection lens
5Full color image displayed on screen
Notes
Filtering process
white lightRGB light RGB light
12345
Light flow
1
2
3
4
5
6
7
   
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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 rangeLens extension
0.84 - 1.03 : 1 zoom lens1.5 - 10 m (4.9 - 32.8 ft)98.5 mm
1.56 - 1.86 : 1 zoom lens2 - 12.4 m (6.6 - 40.7 ft)15.4 mm
1.85 - 2.40 : 1 zoom lens2.5 - 15.9 m (8.2 - 52.2 ft)15.4 mm
2.40 - 4.00 : 1 zoom lens4 - 26.6 m (13.1 - 87.3 ft)73.5 mm
To choose a lens, either calculate the throw ratio required, or use the lens charts provided within this section.
Notes
 For information about individual lens 
part numbers and lens extension 
sizes, see Appendix A at the end of 
this document.
 Lens extension is measured when 
the lens is focused at infinity, and 
fully extended. At other focus 
settings, the extension could be up 
to 10 mm less.
   
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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
0.84 - 1.03 : 1 zoom lens1.5 - 10 m (4.9 - 32.8 ft)
1.56 - 1.86 : 1 zoom lens2 - 12.4 m (6.6 - 40.7 ft)
1.85 - 2.40 : 1 zoom lens2.5 - 15.9 m (8.2 - 52.2 ft)
2.40 - 4.00 : 1 zoom lens4 - 26.6 m (13.1 - 87.3 ft)
3. Ensure the required throw distance is within the range covered 
by the lens.
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 and lens extension 
sizes, see Appendix A at the end of 
this document.
12
1Screen width
2Throw distance
   
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CHOOSING A LENS
Basic calculation example
1. Calculate the throw ratio using the formula.
Your screen is 3.5 m wide and you wish to place the projector 
approximately 6.8 m from the screen. The throw ratio will then 
be
  
6.8
3.5 = 1.94
2. Match the result with the lens table.
The lens matching a throw ratio of 1.94 is the 1.85 - 2.40 : 1 
zoom lens.
3. Check whether the lens covers the required throw distance. 
The range quoted for the 1.85 - 2.40 : 1 zoom lens is 
2.5 - 15.9 m. The required distance of 6.8 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 and lens extension 
sizes, 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
0.84 - 1.03 : 1 zoom lens 1.5 - 10 m (4.9 - 32.8 ft)
1.56 - 1.86 : 1 zoom lens 2 - 12.4 m (6.6 - 40.7 ft)
1.85 - 2.40 : 1 zoom lens 2.5 - 15.9 m (8.2 - 52.2 ft)
2.40 - 4.00 : 1 zoom lens 4 - 26.6 m (13.1 - 87.3 ft)
   
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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 WUXGA DMD™.
When a WUXGA 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:
1.6 (DMD™ aspect ratio)Source 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:
2.35:1 (Scope), 1920 x 817 pixelsTRC < 1, not used
1.85:1 (Flat), 1920 x 1037 pixelsTRC < 1, not used
1.78:1 (16:9), 1920 x 1080TRC < 1, not used
1.66:1 (Vista), 1792 x 1080 pixelsTRC < 1, not used
1.6:1 (16:10), 1728 x 1080 pixelsTRC = 1, not used (native resolution)
1.33:1 (4:3), 1440 x 1080 pixelsTRC = 1.2
1.25:1 (5:4), 1350 x 1080 pixelsTRC = 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
0.84 - 1.03 : 1 zoom lens1.5 - 10 m (4.9 - 32.8 ft)
1.56 - 1.86 : 1 zoom lens2 - 12.4 m (6.6 - 40.7 ft)
1.85 - 2.40 : 1 zoom lens2.5 - 15.9 m (8.2 - 52.2 ft)
2.40 - 4.00 : 1 zoom lens4 - 26.6 m (13.1 - 87.3 ft)
3. Ensure the required throw distance is within the range of the matching lens.
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
Full lens calculation example
Your screen is 3.5 m wide; you wish to place the projector 
approximately 6.8 m from the screen. The source is 4:3.
1. Calculate TRC as follows:
1.6
1.33
TRC = = 1.2
2. Calculate the throw ratio:
6.8
3.5 x 1.2
Throw ratio = = 1.62
3. Find a match in the lens table.
The table shows that the matching lens is the 1.56 - 1.86 : 1 
zoom lens.
4. Check whether the lens covers the required throw distance.
The range quoted for the 1.56 - 1.86 : 1 zoom lens is 
2 - 12.4 m. The required distance of 6.8 m is within the 
range.
Notes
INFORMATION YOU NEED FOR THESE CALCULATIONS
• The TRC formula
• The TRC table (to use instead of the formula)
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
0.84 - 1.03 : 1 zoom lens 1.5 - 10 m (4.9 - 32.8 ft)
1.56 - 1.86 : 1 zoom lens 2 - 12.4 m (6.6 - 40.7 ft)
1.85 - 2.40 : 1 zoom lens 2.5 - 15.9 m (8.2 - 52.2 ft)
2.40 - 4.00 : 1 zoom lens 4 - 26.6 m (13.1 - 87.3 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.
WUXGA images displayed full width
Notes
full width = 1920 pixels
2.35:1(Scope) 
 =  817 pixels
1.85:1 
 = 1037 pixels
16:9 = 1.78:1  
= 1080 pixelsfull height  
= 1200 pixels
   
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SCREEN REQUIREMENTS
WUXGA images displayed with a height of  1080 pixelsNotes
4:3 = 1.33:1 = 1440 pixels
full height 
= 1200 pixels
1.66:1 (Vista) = 1792 pixels 16:10 = 1.6:1 = 1728 pixels
max possible  image height 
 
= 1080 pixels
full width = 1920 pixels
   
Digital Projection M-Vision 930 Series 
Rev C Februar y 2015