Download Laser Harp Digital instrument and Sound generation Adam Langoria Matthew Gann

Laser Harp
Digital instrument and Sound generation
Adam Langoria Matthew Gann
System Overview
• Laser Break Beam
Sensors
• R2R Digital to Analog
Converter
• Virtual Ground and
power amplification
Laser Break Beam Sensors
• Laser Transmitter
– 100Ω Current limiting
resistor
– Laser Diode
– Culminating lens
• Laser Receiver
– 10kΩ pull up resistor
– Active high design
– NPN photo transistors
R2R Digital Analog Converter
• R2R Resistor Network
– 20kΩ and 40kΩ values
– Single Inline Package
– 1% tolerance
Virtual Ground and Amplification
• Virtual Ground
– Low Pass Filter
• 10kΩ and 200μF
• .08 Hz Cut Off Frequency
• Follows the moving average
voltage
• Opamp to sink and source
current
• Amplification
– Opamp
• Unity Gain, gain of 1
• Used for isolation from R2R
network
• Can source and sink much
greater current
Laser Harp
Digital instrument and Sound generation
Adam Langoria Matthew Gann