The liquid crystal screen is arranged in an array relative to the pixels of the lattice liquid crystal, and the pixels of the liquid crystal screen are very free in arrangement and shape. The most common is the "8" field similar to the digital tube. An "8" character is composed of seven pen segments, that is, 7 pixels. The word "rice"

Type "8" is composed of 16 pixels. Of course, the LCD pen segment can be made into any shape, as long as the driving ability of the driver chip permits. Such as the company logo, other patterns, text and so on.

Liquid crystal material production, low price. The driving cost of LCD is also very low. The classic ht1621 series chip is a good choice. Ht1621 can drive 32 × 4 = 128 pen segments, equivalent to 16 "8" characters. Ht1621 interface is serial, there are CS, WR, RD (RD can not be used), data several pins. Ht1621 can also drive the buzzer to produce high and low frequency sound.