Specialist supplier, Display Technology, provides a ten-point guide to purchasing liquid crystal display products.
1) Price
Possibly the most obvious factor when choosing an LCD is cost, but it’s important to recognise that lowest cost does not always provide the best solution. LCD distributors can usually offer discounted pricing, depending on quantities required and the possibility of a future business relationship, but remember, cheaper products may not be legitimate panels from a trusted manufacturer.
2) Stock availability
Most large manufacturer’s will have standard lead times for their products so purchasers should plan their orders to stay within schedule. If there is an ongoing requirement of certain quantities, some suppliers will order in the stock and organise a call off for the customer. Smaller requirements can be unpredictable, so a good supplier will also have some products held in a stock.
3) Choosing a manufacturer
Thin film transistor LCD manufacturers exist in all parts of the world, each targeting different end users. For example, AUO mainly produce industrial TFT displays ideal for use within the industrial, military and automotive sectors. A decent supplier will source products from quality manufacturers and will also provide product roadmaps to help you pick the best display option. Purchase from an official distributor, rather than the grey market, to avoid the disappointment of receiving an inferior product.
4) Understand specifications
Specifications help purchasers ensure the display they choose has the attributes needed. Sometimes attributes are overlooked, however, such as overlooking ambient light conditions when deciding on brightness.
The following factors should therefore be considered carefully: size, aspect ratio, brightness, viewing angle, operating/storage temperature, interface and power consumption. Speaking to a professional can provide guidance on choosing the right TFT display and can also offer alternatives which may not have been considered.
5) Longevity of supply
As with any product, TFT displays can become obsolete or be issued with end of life notices. A good supplier can advise which manufacturers offer the best longevity of supply, but they may also help find the next version of the display or a drop-in replacement. Furthermore, a select few suppliers can mechanically modify a product to meet specific requirements.
6) Supplier flexibility
Price will always be one of the biggest influences on your choice of supplier, so it’s wise to ‘shop around’ by getting quotes from several suppliers. Usually the best pricing is achieved by building a relationship with a supplier through repeat orders. Where possible it is useful to give the supplier your target cost, which can save time for you and the supplier.
7) Financial security
In most cases, suppliers will credit check customers to ensure they can pay for their orders, but in fact, customers should also check their supplier to ensure they have the financial strength to supply an order. Using a tool to credit check a supplier can provide peace of mind about their cash flow and provides an opportunity to address any concerns with the supplier.
8) Support products
Displays are usually part of a larger design, so it is advantageous for suppliers to have a range of products to support a TFT display. This means purchasers can find all the required support products in one place, potentially with the benefit of reducing costs. Support products can include: interface cards, TFT controllers, power supplies, cables and LED backlight drivers, some of which may be available as an easy to install kit.
9) Support services
Choice of supplier can also be influenced by the services available to add value to the solution. For example, if you need to integrate a touch screen into your solution but don’t have the facilities to do this in-house, you need a supplier that can provide a touch screen fitting service. Similarly, if you are looking to improve readability, you would choose a supplier that can optically bond the display.
10) Technical support
No matter what experience you have, it is important that the supplier you purchase from can offer technical support after purchase, either over the phone or in person. Speaking to the supplier ensures you follow correct procedure to avoid damaging panels further. Some suppliers also offer a repair and return service or a warranty.