1.3.1.1.3 Disadvantages

Limited viewing angle, causing color, saturation, contrast and brightness to vary, even within the intended viewing angle, by variations in posture.

Uneven backlighting in some (mostly older) monitors, causing brightness distortion, especially toward the edges.

Black levels may appear unacceptably bright because individual liquid crystals cannot completely block all light from passing through.

Only one native resolution. Displaying any other resolution either requires a video scaler, causing blurriness and jagged edges; or running the display at native resolution using 1:1 pixel mapping, causing the image either not to fill the screen (letterboxed display), or to run off the lower right edge of the screen.

Fixed bit depth, many cheaper LCDs are only able to display 262,000 colors. 8-bit S-IPS panels can display 16 million colors and have significantly better black level, but are expensive and have slower response time.

 Low refresh rate. All but a few high-end monitors support no higher than 60 or 75

Hz; while this does not cause visible flicker due to the LCD panel's high internal refresh rate, the low input refresh rate still limits the maximum frame-rate that can be displayed, negatively impacting gaming and 3D graphics.

 Dead or stuck pixels may occur during manufacturing or through use.

Subject to burn-in effect, although the cause differs from CRT and the effect may not be permanent, a static image can cause burn-in in a matter of hours.

In a constant-on situation, thermalization may occur, in which part of the screen has overheated and looks discolored compared to the rest of the screen.

Loss of brightness and much slower response times in low temperature environments. In sub-zero environments, LCD screens may cease to function without the use of supplemental heating.

 Loss of contrast in high temperature environments.

 Not usually designed to allow easy replacement of the backlight.

Poor display in direct sunlight, often completely unviewable. Transflective LCDs provide a large improvement by reflecting natural light, but are dimmer when relying on the backlight and so they have only been adopted for specific outdoor uses.

 Cannot be used with light guns/pens.

 Hard to read when wearing polarized sunglasses.

1.3.2 Official boards

The original Arduino hardware is manufactured by the Italian company Smart Projects. Some Arduino-branded boards have been designed by the American company SparkFun Electronics.Sixteen versions of the Arduino hardware have been commercially produced to date.

Example Arduino boards:

 Arduino Uno

 Arduino Mega 2560

 Arduino Fio

 Arduino Leonardo and Micro

 Arduino Esplora

 LilyPad Arduino USB

 LilyPad Arduino

 Arduino Mini

 Arduino Nano

 Arduino Pro

 Arduino Pro Mini

1.3.2.1 Arduino Mega 2560

Figure 1. Arduino Mega 2560 Front

Figure 2. Arduino Mega 2560 Back