Quarterly Question
Q: Using a yellow/black display as an example, what determines the yellow color and black background in a ChLCD product?
A: The simple and short explanation is that a monochrome ChLCD has two visible states: the bright state and the dark state. The bright state is called the planar state and is reflective. The dark state is the focal conic state and it is approximately 90% transmissive.
The planar state: When an electric field is applied to the display the cholesteric liquid crystal material molecular chains “twist” into helical structures. The wavelength of light reflected by the liquid crystal material is directly proportional to the pitch of the helix.
In the case of the yellow/black display the pitch is such that the light reflected is in the yellow portion of the visible spectrum. In the focal conic state, the transmissive state, ambient light passes through the top substrate, through the cholesteric liquid crystal material and is absorbed by the black back coating on the back surface of the bottom substrate.
In this example, those pixels in the bright state (planar) reflect yellow light and those pixels in the dark state (focal conic) pass all wavelengths of light which are absorbed by the back coating.
A third state called the homotropic state plays a key role in all ChLCD products permitting the switching from the focal conic state back to the planar state. That topic will be covered in a future edition of The Liquid Twist.
If you have a question regarding Kent Displays' products or technology please submit your questions. We will select a question from those submitted and publish it along with the answer in a future newsletter.
Announcements
Society of Information Displays International Symposium, Seminar and Exhibition 2006
Kent Displays, Inc. will exhibit at SID 2006 occurring within the Moscone Convention Center San Francisco, California June 4-9, 2006. Our standard product line as well as our latest technology developments will be on display at Booth #1016.
Think Flexible.
Register to win a USB flash drive featuring a “No Power” ChLCD. Drawings will be held daily and the winner need not be present. Non-attendees can register to win at smartdrive@kentdisplays.com .
Presenter: Joel Domino
May 12, 2006
San Jose, CA
SID International Symposium
Title: Flexible Ink Jet Printed Conductive Polymer Electrode Cholesteric Display
Presenter: Dr. Erica Montbach
Jun 4, 2006 – Jun 9, 2006
San Francisco, CA
SID International Symposium
Presenting: Recent Progress in Flexible & Drapeable Reflective Cholesteric Displays
Presenter: Dr. Asad Khan
Jun 4, 2006 – Jun 9, 2006
San Francisco, CA
Great Lakes Photonics Symposium
Presenting: A Review of Advances in Flexible Cholesteric Displays
Presenter: Dr. Asad Khan
Jun 12, 2006 – Jun 16, 2006
Dayton, OH |
Editor's Notes
Welcome to the Volume 2, issue 2 of Kent Displays, Inc. Quarterly Newsletter: The Liquid Crystal Twist. As the world leader in the research, development and manufacture of Cholesteric Liquid Crystal Display products, it is our hope to bring you interesting and useful information regarding ChLCD technology, products, distributors/representatives and customers each quarter.
In the News
New Retail Product Website Launched Featuring Products Incorporating “No Power” Cholesteric Liquid Crystal Displays.
Kent Displays, Inc. has launched an internet presence at www.nopowerdisplays.com for the sales and marketing of retail products using our ChLCD technology. The initial featured product is Carry Computer's Didigo USB SmartDrives. The High Speed USB 2.0 Flash Drive is available with 256 MB, 512 MB or 1 GB capacity. Each Drive incorporates a “No Power” Cholesteric Liquid Crystal Display with a changeable eleven character display area for use as a personalized label. A pie chart indicates available memory space and a four digit area details free memory space in megabytes.
Consumers can purchase online at: www.nopowerdisplays.com . Other products incorporating ChLCDs will be announced at this website in the near future.
SID 2006 Theme: Think Flexible!
For 43 years The SID International Symposium, Seminar and Exhibition has been the premier event of the electronic-display industry. Seemingly every noteworthy leap forward in display technology has been announced and demonstrated at SID. This year will be no different as Kent Displays will feature what many industry experts consider revolutionary and soon to be commonplace - flexible ChLCD products.
 
Until recently "flexible displays" brought to mind conventional LCD with plastic substrates instead of glass. Kent Displays’ method of encapsulation of cholesteric liquid crystal material not only makes plastic substrate ChLCD products possible today but also redefines the term flexible to include single substrate products. Ultra flexible, conformable, super thin and light weight single substrate displays can be made on virtually any kind of material including plastic, paper and textile including woven and non-woven materials. See for yourself at SID June 6th – 8th in San Francisco, CA.
The future is closer than you think – Kent Displays will produce plastic ChLCD products by Q1 of 2007.
SPIE awards Kent Displays “Best Paper Award 2006”.
SPIE – The International Society for Optical Engineering - awarded its “Best Paper Award 2006” to Kent Displays, Inc. at its Future Displays Technologies Conference held last week in the Orlando, Florida area. Dr. Asad Khan presented Recent Advances in Flexible Low Power Cholesteric LCDs. Congratulations to Dr. Khan and the entire team!
The 2006 Embedded Systems Conference Silicon Valley USB SmartDrive winners:
Jesse Laird
Mini Mitter
Bend, OR
Mike Treppa
Smiths Medical
St. Paul, MN
John Chapman
Invensys Climate Controls
Plain City, Ohio |
