Electronics notes/Touch screen notes

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This is for beginners and very much by a beginner. It's meant to try to cover hobbyist needs, and as a starting point to find out which may be the relevant details for you, not for definitive information.

Some basics and reference: Volts, amps, energy, power · Ground · batteries · resistors · changing voltage · transistors · fuses · diodes · varistors · capacitors · inductors · transformers · baluns · amplifier notes · frequency generation · skin effect


And some more applied stuff:

IO: IO and wired communication · localish communication · wireless (ISM RF, GSM, RFID, more) · 802.11 (WiFi) · 802.15 (including zigbee)


Sensors: General sensor notes, voltage and current sensing · Knobs and dials · Pressure sensing · Temperature sensing · humidity sensing · Light sensing · Movement sensing · Capacitive sensing · Touch screen notes

Actuators: General actuator notes, circuit protection · Motors and servos · Solenoids

Some stuff I've messed with: Avrusb500v2 · GPS · Hilo GPRS · Bluetooth serial · JY-MCU · DMX · ESC/POS notes

Audio notes: basic audio hacks · microphones · amps and speakers · device voltage and impedance, audio and otherwise ·

Less sorted: Common terms, useful basics, soldering · Microcontroller and computer platforms · Arduino and AVR notes · ESP series notes · Electronics notes/Phase Locked Loop notes · mounts, chip carriers, packages, connectors · signal reflection · pulse modulation · electricity and humans · Unsorted stuff


See also Category:Electronics.

Types

http://en.wikipedia.org/wiki/Touchscreen#Technologies


Resistive

Capacitive

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

Meant for any conductor -- anything that can be/influence capacitance, meaning fingers or anything with a conductive tip - from specific styluses to sausages in latex gloves.

Designs usually try to only be sensitive to very nearby things (not far beyond a protective plastic/glass layer.


Has a few subtypes -- see capacitive sensing. One of them can be multi-touch, and multi-touch tablets are very usually capacitive.


Touch capacitive can be faster and more responsive than resistive. Some of the simpler/cheaper designs are less accurate than resistive, though.

The screen itself can be built in a more robust way than resistive (sensors are under the top glass, not part of the top layer as in resistive).


Went from rare to pretty common in a few years (late noughties). Used e.g. in trackpads, and recently quite a bit in MP3 players, phones (although resistive can be better for handwriting recognition).

Optical

Acoustic

Temperature sensing

Brand-specific notes

Elo notes

eGalax notes