09-10-2012, 05:22 PM
IR Sensor
[attachment=35851]
IR Sensor (IR Receiver and IR Emitter)
The basic principle of IR sensor is based on an IR
emitter and an IR receiver. IR emitter will emit infrared
continuously when power is supplied to it. On the other
hand, the IR receiver will be connected and perform
the task of a voltage divider. IR receiver can be
imagined as a transistor with its base current
determined by the intensity of IR light received. The
lower the intensity of IR light cause higher resistance
between collector-emitter terminals of transistor, and
limiting current from collector to emiiter. This change
of resistance will further change the voltage at the
output of voltage divider. In others word, the greater
the intensity of IR light hitting IR receiver, the lower
the resistance of IR receiver and hence the output
voltage of voltage divider will decreased. Usually the
IR emitter and IR receiver will be mounted side by side,
pointing to a reflective surface. The further distance
away between emitter and receiver decrease the
amount of infrared light hitting the receiver if the
distance between the sensor and a reflective surface is
fixed.
GETTING STARTED
User can obtain the hardware set for this project (PR4)
either by online purchase (www.cytron.com.my) or get
it from Cytron Technologies Shop. No PIC
microcontroller, programming and soldering required
in this project.
1. Once user has the hardware set, user may start
plug in the electronic components on the
protoboard. Protoboard is a fundamental tool
for beginner to develop their mini project,
where no soldering is required. Plug the
electronic components on breadboard
according to the schematic. Voltage regulator
7805 is used to generate 5V from a 9V battery
as power source for the circuit. Schematic is
provided in Cytron website.
[attachment=35851]
IR Sensor (IR Receiver and IR Emitter)
The basic principle of IR sensor is based on an IR
emitter and an IR receiver. IR emitter will emit infrared
continuously when power is supplied to it. On the other
hand, the IR receiver will be connected and perform
the task of a voltage divider. IR receiver can be
imagined as a transistor with its base current
determined by the intensity of IR light received. The
lower the intensity of IR light cause higher resistance
between collector-emitter terminals of transistor, and
limiting current from collector to emiiter. This change
of resistance will further change the voltage at the
output of voltage divider. In others word, the greater
the intensity of IR light hitting IR receiver, the lower
the resistance of IR receiver and hence the output
voltage of voltage divider will decreased. Usually the
IR emitter and IR receiver will be mounted side by side,
pointing to a reflective surface. The further distance
away between emitter and receiver decrease the
amount of infrared light hitting the receiver if the
distance between the sensor and a reflective surface is
fixed.
GETTING STARTED
User can obtain the hardware set for this project (PR4)
either by online purchase (www.cytron.com.my) or get
it from Cytron Technologies Shop. No PIC
microcontroller, programming and soldering required
in this project.
1. Once user has the hardware set, user may start
plug in the electronic components on the
protoboard. Protoboard is a fundamental tool
for beginner to develop their mini project,
where no soldering is required. Plug the
electronic components on breadboard
according to the schematic. Voltage regulator
7805 is used to generate 5V from a 9V battery
as power source for the circuit. Schematic is
provided in Cytron website.