5 Factors to Consider Choosing a Small LCD Display

The Small LCD Display is Becoming More Popular

Cell Phones are not the only market for a small LCD display. Medical, industrial, Automotive, Consumer, Audio/visual and even coffee machines now require a small LCD display.

At a recent visit to the doctor’s office I noticed a small device to measure pulse rate. The display was blue and white, negative mode, that not only displayed the pulse rate, but also a graphical monitor to represent the rise and fall of the heart rate. The dimensions of this tiny device measured about 20mm by 10mm. No cords or wires, it simply clipped onto the patients finger.

In the past I had always seen a large TFT or CRT display on the wall of the doctor’s office. There would be a cord from the outlet to the large display and a second cord from the display to the person’s arm or finger. I would assume the cost of the pulse monitor with the larger display would be 10X greater.

Small LCD Display Technology Driven by the Cell Phone Market

Cell phones require small LCD Displays. Some cell phones contain a dual LCD display, as in flip phones that display the name of the caller. Cell phone displays have moved from older monochrome STN or FSTN technology to TFT and OLED’s (organic light-emitting diode) and now AMOLED’s (Active-matrix OLEDs). As the technology of the display evolves, the brightness of the color and the contrast increase. It is amazing how much detail can be seen in a small TFT/OLED display that measures no more than 1.7 inches in the diameter.

When a cell phone manufacture such as Sony, Sharp, Samsung, LG and the little known one that is named after a small fruit, Apple, build a new product, they build it by the boat load. Cell Phones are manufactured in quantities as high as 1,000,000+. This means that the display chosen for that phone has a lower cost than other similar sized small LCD displays that are not manufactured in as great of quantity. This makes it attractive for other OEM’s with lower quantity requirements to design in the same display as that being used by cell phone users. The OEM realizes a cost savings.

Small LCD Display vs Large LCD Display – Pricing Comparison

As a general rule, no. In the past, the size of the glass was the main factor in display cost. It would make sense that a small LCD display would cost less than a larger display since the smaller the glass, the less the cost. But this is becoming more of the exception than the rule. As the display becomes smaller there are several factors that increase its cost and, in some cases, lead time. The main factor is the quantity of displays being manufactured.

Small Color LCD displays Need to be Manufactured in Large Quantities to be Affordable

Small mono-chrome (non-color) LCD displays have lower MOQ’s (minimum order quantity) in the neighborhood of 1K to 10K. This is not true with color displays. If the LCD manufacturer is building high volumes of a small color display for other customers, then you would be able to purchase this display at a lower cost. On the other hand if you designed your own custom color LCD display, you could count on MOQs of several thousand. The exception to this is with FSC (Field Sequential Color LCD Technology). This new technology offers lower MOQ’s of 500 displays.

I only need 500 or 1,000 of a Small LCD display, what is a good fit?

1. If this is a color display such as TFT/OLED/AMOLED, ask the manufacture what standard size displays they carry that is close to what you need.
2. Make sure you ask what the MOQ is and most important, what is the life-time of this display or EOL (End of Life). How long will they continue to manufacture this display? The last thing you want to do is design in a display for your new product only to find out you must make a last time buy.

For additional information or design support for your small LCD display. Contact Focus LCDs at 480-503-4295.