New TFT displays have 300 : 1 contrast ratios'

1
(No Transcript)
2
Display enhancements shouldnt be required

• New TFT displays have 300 1 contrast ratios.
• Brightness has increased to 350 nits.
• Other viewing improvements have been added.

So there isnt any reason to improve the display,
right???
3
High ambient / outdoor applications have unique
requirements

• Outdoor applications require sunlight
  readability.
• Protective overlays are often used.
• Touch switches are common options.
• High Bright Backlights are popular options and
  necessary to more closely match surround
  illuminance, but do not solve contrast problems
• Outdoors is a harsh environment

4
High Ambient Applications and Markets
Automotive / GPS
Avionics
Kiosks / ATMs
In-Vehicle Computers
Gas Pump POS
Outdoor Kiosk
5
What is a nit?
A nit is a unit of projected light energy from
one candle, measured from its source,measured one
meter away, measured over a one meter square
area. A footlambert is the same light measured
one foot away, over a one foot square area. 1 ft
lambert is the same as 3.426 nits
6
Contrast ratios two methods, two results
Extrinsic Contrast Ratio A reading from a
distance, taking into account ambient light and
reflections. A good extrinsic contrast ratio is
10 1. Newsprint is about 1.31.
Intrinsic Contrast Ratio On the surface, the
display, may read a 3001 contrast ratio. This
does not take into account ambient lighting. In
addition, the light meter is measuring total flux
regardless of angular distribution
7
Brightness versus Contrast

• The human eye perceives brightness
• The human eye sees contrast
• The eye can perceive approx. 100 levels of
  brightness each level must be twice as bright as
  the other.
• The eye can see over 1 billion levels of
  contrast

8
Brightness versus Contrast corrected

• The human visual system includes both the eyes
  and complex information processing in the brain.
  This is called the visual system.
• The human eye sees brightness differences. We
  call these brightness differences contrast.
• The human visual system can see over 1 billion
  levels of contrast

9
Brightness versus Contrast

• Brightness lightens or darkens the image.
  Contrast changes the distinction between the
  light and dark areas.
• The human eye eventually becomes saturated with
  brightness and becomes more responsive to
  contrast.
• Contrast ratio is much more significant than
  brightness in high ambient illumination
  environments.
• The human visual system amplifies the difference
  in contrast lateral inhibition

10
Lateral Inhibition Test
You should only see a monochrome gray bar
11
Lateral Inhibition Test
Is the bar still monochrome?
12
Contrast Example
This is a test
High contrast, easy to read
This is a test
Very low contrast but it is readable
13
Luminance vs. Illuminance

• 1500 nits is read only on white
• Black level can go as high as 100-150 nits
• In a darkroom, this is only 15 1 contrast ratio

1500 nits
Light coming out of a display is luminance
14
Effects of llluminance
10,000 ft Candles
Ambient light is illuminance
5 reflection
1500 nits
5 reflection adds to the white level but also
to the black level, lowering the contrast
ratio, washing out the display
15
Formulas
Reflection 5 x of surfaces x ambient light
Contrast Ratio
16
Even with high bright backlights, contrast may be
low
17
Direct Bonding eliminates reflective loss and
increases contrast
Reflection 10K ftC x 2 R 50 nits
5
5
15000.85 50
26 1 Contrast
5
50
1500 nits
Direct bonding eliminates the two internal points
of reflection. With AR coatings on the front,
overall reflections drops to less than 2
18
Touch Screen Issues
Transmissivity is only one of the problems
1200.85 2500
1.4 1
2500
1500 nits
1200 nits

• Resistive touch has 4 layer, two outer and two
  internal layers, each reflecting 5 each
• Additionally, the transmissivity is lowered by
  20
• This bring the contrast ratio to 1.5 1

19
Touch Screen Issues
Transmissivity is only one of the problems
1200.85 1500
1.68 1
1500

• Resistive touch has 4 layer, two outer and two
  internal layers, each reflecting 5 each
• Additionally, the transmissivity is lowered by
  20
• The contrast ratio to 1.68 1, an improvement,
  but not by much
• Optically enhanced touch screens can help

1200 nits
1500 nits
20
G-BOND LaminationBenefits

• G-BOND lamination eliminates two (or more)
  internal layers which cause reflection and thus
  washout of the display.
• G-BOND has the best reflection reduction of any
  commercially available technology.
• G-BOND is among the lowest cost processes for
  glass bond lamination
• Creates an environmental seal
• Reinforces the LCD cell, making it much more
  rugged.

21
Direct Bond Benefits

• Low reflective loss means higher contrast in high
  bright environments
• Display are daylight readable at 500 nits,
  sunlight readable at 800 nits
• Backlight power can be lowered to reduce overall
  power draw and less heat production
• No air gap eliminates greenhouse effect heat
  rise.
• Solid bond will conduct heat out of the display
• Cooler displays will not clearor go isotropic
  as quickly.
• No air gap prevents moisture from forming under
  the window.

22
Silicone Direct Bond

• Reworkable through production process
• Reworkable in post-production
• Low toxicity, environmentally friendly materials.
• Excellent UV resistance
• Excellent optical properties
• Excellent mechanical properties
• Low glass transition temperature

23
Clearview Display Offers

• Bonded Anti-reflective glass
• Diffused AR glass
• Chemically strengthened glass
• Infrared blocking glass
• Bonded touch screens- Should be optically
  enhanced
• EMI/RFI windows
• Film laminations

24
(No Transcript)