Smartphone and Gadget Repair at Computer Catering (Up to 55% Off). Three Options Available.


from $49
Value Discount You Save
$100 51% $51
Limited time remaining!
Over 20 bought
Limited quantity available

Choose from Three Options

  • $49 for iPhone 3, 4, 4S screen replacement ($100 value)
  • $59 for iPad 2, 3, or 4 screen replacement ($130 value)
  • $25 for $50 worth of phone repair

Liquid Crystals and LCDs: How Cell Phones Resemble Carrots

A smartphone's tiny screen relies on the strange properties of liquid crystals. Check out Groupon's study of LCDs to learn how they create the vivid pictures in your pocket.

The term liquid crystal seems a contradiction, but a liquid crystal is actually neither a liquid nor a solid—it's both, stuck in a sort of chemical limbo with its molecules somewhere between the liquid and solid phases. When an electrical current passes through a liquid crystal, its molecular orientation changes, and so does the direction of light that passes through it. By sandwiching these crystals between polarized glass and manipulating the current passing through them, your phone is able to control the light they channel, resulting in the high-contrast images that appear on screen. Although our brains only see each pixel as a single dot, each consists of red, blue, and green subpixels that, when lit at various intensities, can emit more than 16 million colors.

Despite their advanced applications, liquid crystals are not a recent discovery. They were first identified in the late 19th century by a scientist studying cholesterol extracted from carrots—a natural source of liquid crystals, as are human beings and most other living things, which tend to have them in their cell membranes. Liquid crystals and LCDs were the subject of research and patent applications throughout the early 20th century—including one filed by Marconi’s Wireless Telegraph Company in 1936—and finally hit consumer electronics in the early 1970s, when they were introduced in wristwatches.

Tips from Groupon Customers

  • “They are very nice!”

  • “Very pleasant and service was done within an hour. I will use them for my computer needs.”

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    329 Gill Street

    Alcoa, Tennessee 37701


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In a Nutshell

Expert technicians replaced cracked and broken screens on the iPhone 3, 4, and $s, and well as iPads

The Fine Print

Expires 180 days after purchase. Appointment required, same day appointments accepted. Merchant's standard cancellation policy applies (any fees not to exceed Groupon price). Limit 1 per person, may buy 1 additional as gift. Must use promotion value in 1 visit. Valid only for option purchased. All goods or services must be used by the same person. General spend voucher covers iPhone 5, other brand cell phones and tablets, laptops, computers, game consoles, small TVs. Deal does not include LCD repair for iPads (does for iPhones). Merchant is solely responsible to purchasers for the care and quality of the advertised goods and services.

High-tech products, such as smart phones and GPS receivers
Choose your deal:
iPhone 3, 4, 4s screen replacement
$100 list price - 51% off - Save $51
9 bought
iPad 2, 3, or 4 screen replacement
$130 list price - 55% off - Save $71
Over 10 bought
$50 Groupon toward service
$50 list price - 50% off - Save $25
1 bought