NDSL
The NDSL is a smaller version of the hand-held Nintendo DS system. The NDSL features the same basic design as the standard NDS, although it is smaller and thinner. It is powered by two AMD processors running at 67 MHz and 33 MHz respectively. The device has stereo speakers located on the bottom left side. The NDSL sports two 3.12-inch LCD screens, one on the top of the device and one on the bottom.
LCD Screens
Each of the NDSL's two screens is the same size, and each has the same resolution: 256 by 192 pixels. The screens have a dot pitch of 0.24 mm. Dot pitch is the measure of the distance between clusters of pixels, where each cluster is composed of a group of red, green and blue pixels. With a dot pitch of 0.24 mm, the LCD screens are each capable of displaying 262,133 discreet colors. Of the two screens, only one contains the additional component known as a digitizer.
Digitizer
In-game, the lower LCD screen displays menu screens, maps and other helpful game-specific objects. The digitizer is a transparent film applied to the bottom of this screen that makes it possible to interact with these objects. Without the digitizer, you would have no way of selecting game options, as the upper LCD screen is dedicated to graphics only. The digitizer and the NDSL's magnetic stylus work together to accomplish this feat.
How it Works
The digitizer is in a class of devices known as "analog touch screens." It continually emits a series of magnetic pulses that the electronics within the stylus can detect. The stylus contains a coil that responds to the electromagnetic field, and this interaction creates a small amount of electricity within it. The digitizer detects the exchange, and it calculates the pen's location. When you press a button on the digitizer's screen, a small pressure sensor within the pen transmits data to the NDSL, telling it how hard you are pressing.