Sensors; Camera Sensor; Specifications; Measurement Process - Libelium Waspmote Technical Manual

3. Sensors

3.1. Camera Sensor

3.1.1. Specifications

Width(min.): 24mm
Height: 24mm
Length: 17mm
Max resolution: 640x480 for pictures, 320x240 for video
Image Sensor Analog Voltage: 3,3V
Image Sensor Digital I/O Voltage: 2,8V (from Waspmote 3G/GPRS board)
Temperature range:
operating: -30°C to 70°C junction temperature
stable image: 0°C to 50°C junction temperature
Consumption (active): 48 mA
Angle of view: 70º

3.1.2. Measurement Process

The image sensor is fully managed by Waspmote 3G/GPRS board. Please, refer to API chapter for more information.

3.2. Luminosity sensor

3.2.1. Specifications
Resistance in darkness: 20MΩ
Resistance in light (10lux): 5 ~ 20kΩ
Spectral range: 400 ~ 700nm
Operating Temperature: -30ºC ~ +75ºC
Minimum consumption: 0uA approximately

3.2.2. Usage

With this sensor we can know the level of visible light and we can decide if switch on or switch off the blocks of IR LED.
3.2.3. Measurement process
This is a resistive sensor whose conductivity varies depending on the intensity of light received on its photosensitive part. The
measurement of the sensor is carried out through the analog-to-digital converter of the microcontroller, reading the resulting
voltage out of a voltage divider formed by the sensor itself and the load resistor of 10kΩ.
The measurable spectral range (400nm – 700nm) coincides with the human visible spectrum so it can be used to detect light/
darkness in the same way that a human eye would detect it.
The sensor value can be read with the next function:
{
LDR_value = readAnalog(SENS_LDR);
}
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Sensors
Figure : Camera sensor with IR
cut filter and lens
Figure : Light sensor LDR
v4.3