A lot of consumers wonder how manufacturers determine the LCD display panel prices. After all, display solutions such as TFT LCDs and HMI touch screens do not always come cheap. And sometimes, a few products that can indeed be purchased for lower prices may come with several quality issues.
Hence, we’ve rounded up a list of factors that influence how to display modules such as TFTs, LCD, and touch screens are priced. You can also use these factors to evaluate to whom you should place your next orders for your display solutions.
1. Fluid types used in LCD panels
One major determiner for the LCD display price is the fluid type used inside the panels.
LCD fluids are used in altering the light orientation passing through glass substrates. Hence, this causes the panel’s active pixels to darken. Different kinds of LCD panel fluids provide unique characteristics and change a panel’s viewing angle, temperature range, and display clarity.
Now, LCD panels may contain any of these fluid types:
a. Twisted Nematic (TN)
Twisted Nematic (TN) fluid is among the earliest developed fluid technologies used in LCD panels.
TN fluid contains liquid crystal substances that allow light to pass through by twisting and untwisting at a 90-degree angle. This display technology is available in monochrome; that is, black characters against a gray background.
The viewing angle is limited in a panel containing TN fluid. This means that the text or image display becomes harder to read if you rotate the device away from its center. The display is also not that sharp compared to displays using other technologies.
Another characteristic of this fluid is that it works well even in colder temperatures. It’s because TN fluid has the quickest response time among the other LCD fluid types.
TN fluid is considered the cheapest LCD fluid type. However, this doesn’t mean that TN isn’t widely used. The display technology is greatly utilized in digital clocks, pagers, and gas pumps.
b. Super Twisted Nematic (STN)
STN fluid works primarily the same way as Twisted Nematic fluid. However, the liquid crystal components are twisted at a 270-degree angle.
LCD modules with STN fluid enjoy a wider display angle, greater multiplexing, higher image contrast, and sharper response than devices using TN fluids. However, modules with STN fluids may have slower response times when used in lower temperatures due to the fluid freezing inside the device.
STN fluid falls under the moderately cheap LCD module price. Furthermore, STN fluid is widely utilized in several monochrome LCD devices such as POS machines, inexpensive feature phones, and informational screens of some devices.
c. Color Super Twist Nematic (CSTN)
The CSTN fluid technology takes away the monochrome finish of the typical STN fluid devices. Red, green, and blue filters are added to the fluid module to allow a colored display. New versions of CSTN often feature a viewing angle of 140 degrees and 100ms response times.
CSTN is a bit pricier than TN and STN fluids. But it’s a good choice if you need to display color images on your LCD device. In fact, a lot of color feature phones use CSTN as an alternative to the TFT displays, saving almost half the manufacturing costs.
d. Film-Compensated Super Twisted Nematic (FSTN)
FSTN fluid type is similar to STN by nature. However, it has an added retardation film layer to improve contrast and viewability.
A device using FSTN fluid has better viewing angles and can produce a sharp black-and-white coloration. It is a good choice for devices that need to display small yet easy-to-read images.
In terms of cost, the LCD display module price of a unit with FSTN is higher compared to TN and STN. But this is concerning the better visual quality that FSTN offers.
To cap off this part, the fluids used in a screen is a big factor in determining the overall LCD screen display panel price. As you can see, the four fluid types often used in LCD screens rise in costs with respect to the visual quality produced by each technology.
2. Temperature Range
The temperature range in which LCD screen displays may work varies intensely. Some displays continue to work at optimal performance even when used in cold or hot outdoor temperatures. Lower-quality LCD panels may start having glitches at the slightest change of temperature and humidity. Hence, the temperature range may have a huge impact on the LCD display panel price as well.
What happens to the LCD fluid and other screen components in extreme temperatures?
- In hot environments– The liquid crystals may begin to deteriorate, while the electrical components will start overheating and cause damage to the display screen performance.
- In cold environments– LCD fluid may begin to crystallize and freeze. Components may also freeze and stop working altogether.
Now, most LCD screen panels don’t experience such temperature extremes. In fact, a typical LCD TV can operate properly between approximately o°C and 32°C (32° – 90° F). Meanwhile, other screen modules (usually the industrial-grade ones) have unique capabilities to work in even more extreme ends of the temperature scale.
If you want to look for the most cost-effective type of LCD panel for your device, then you must consider the following standard LCD unit temperature types:
a. Normal Temperature
Normal temperature units work well in environments that have indoor temperatures at approximately 20-35°C (68-95°F). Some LCD modules may work well above up to 50°C (122°F). Such LCD modules can be used in daily settings by the typical consumer public.
b. Wide/Extreme Temperature
LCD units under this type are made to withstand lower and higher temperature ranges. Extreme operating temperatures may range anywhere from -30°C to 85°C (-22-185°F). Most LCD modules with wide/extreme temperature capabilities are used in extremely cold areas such as Artic places and ski resorts, as well as humid and moisture-rich hot outdoor areas.
Generally, the LCD module price goes up if the entire display unit can withstand higher temperature ranges. Those who can operate under normal temperature ranges only are usually cheaper.
Hence, you must consider the places where you’ll be installing your LCD display devices. You can’t just use cheaper LCD modules for an industrial-grade display machine. Treat your LCD panel as an investment and select a panel that will yield better screen performance that’ll last several years for you and your business.
3. Color display capability
Another key factor to consider in the wide range of TFT LCD display price is the module’s color display capability.
It’s an unspoken rule, but monochrome modules are generally cheaper than color-capable ones. However, color-capable display modules may also have cost variations depending on their display capabilities.
Color LCDs have three subpixels that hold red, blue, and green color filters. Each subpixel can have as much as 256 color shades, depending on the variation and control of the voltage applied to it.
Now, when you combine 256 shades of both red, blue, and green subpixels, color LCDs can display a color palette of up to 16.8 million colors. And all these are made possible by millions of transistors etched onto the glass modules.
Display size also plays a large role in an LCD device’s color capability. Smaller screens need fewer pixels and transistors since they have smaller display sizes. These screens are also less costly to make. Now, larger screens with high color resolution and huge display sizes require more transistors and pixels, justifying the higher prices of such monitors.
4. Touch screen capability
A touch screen display module is more costly than a non-touch monitor module. Touch capability is integrated into Human Machine Interface (HMI) modules and is generally used in kiosks, bank ATMs, hospital equipment, and similar devices in other industries.
HMI touch screen price is also dependent on what kind of touch screen technology it uses. Here are some of the common touch technologies integrated to HMI touch screen devices:
This type of touch screen technology is made up of a top polythene layer and a glass-bottom layer separated by microdots or an air gap. This module is then attached to a touch screen controller.
Resistive touch screen panels are used in most bank ATMs and some older models of cellular phones. They carry the lowest HMI touch screen price among all other touch screen technologies.
However, resistive touch screens may have downsides such as their proneness to damage and poor response to light touches.
Capacitive touch screens are the most common in the display industry today. This technology uses transparent conductors, insulators, and glass to create the panel. An electrostatic field change in the screen’s module happens when a human finger touches the screen surface. This ultimately creates signals that are sent to the touch screen controller for processing.
In general, capacitive touch screens are the most cost-effective choice for HMI machines. Since they are considered the gold standard of commercial touch screen technologies, they do come with a high price tag.
However, capacitive HMI touch screen price can still vary depending on the type of capacitive technology used (surface capacitance, PCT/PCAP, self-capacitance PCT, or mutual capacitance PCT).
c. Infrared Grid (IR)
Infrared grid technology uses photodetector pairs and X-Y infrared LED components to allow sensors to pick up the touch and its exact location. Infrared grids have been used in several touch screen modules before the capacitive touch screen technology took over.
Now, infrared grid technology became a more budget-friendly alternative to other popular touchscreen technologies.
Several factors determine the LCD display panel price. They include:
- LCD panel fluid type
- Temperature operating capacity
- Color capability
- Touch screen technology used
We’ve explained the following factors at length for both public consumers and business clients to understand the variations in TFT, LCD, and HMI touch screen prices.
Cheap doesn’t necessarily mean low-quality. Also, expensive options aren’t always a wise choice, either. You can maximize your buying or manufacturing options if you know how to compare LCD modules and panels depending on the specifications you truly need for your display machines and devices.