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Brightness and UV Sensor

On this senseBox component, two sensors are combined.

The light intensity is measured with the TSL45315 sensor from AMS-TAOS or the LiteOn LTR329ALS-01 sensor (since 02/21). This sensor detects the light conditions similar to the human eye and outputs the brightness values directly in Lux, with a large dynamic range (3 Lux to 220k Lux).

The second sensor is a Vishay VEML6070 Ultraviolet (UV) light sensor. This sensor converts the intensity of the sun's UV light into digital data. The sensor has excellent UV sensitivity and linearity over Filtron™ technology. It has good UV radiation measurement even with long sun UV exposure and can excellently compensate for temperature fluctuations.

Licht Sensor

Brightness and UV Sensor

Technical Information​

Light Meter​

  • 3.3V - 5V tolerant I2C/TWI interface
  • Input voltage range: 3.3V - 5V
  • On-board 2.5V voltage regulator
  • On-board level shifter

UV Sensor​

  • Operating voltage: 2.7V - 5.5V I2C interface
  • Supports acknowledgment function (Active Acknowledge function)
  • Temperature compensation: -40°C to +85°C
  • Software shutdown control for immunity to flickering fluorescent lights

Dimensions​

  • 25mm x 25mm x 9mm
  • Weight: 2.5 g

Connection​

i2c port

The component is connected to the I2C port.

Programmierung (Arduino)​

Software Library​

To program the sensor in Arduino, you need to install the software libraries Adafruit LTR329 and LTR303 and Adafruit VEML6070 Library.

Code​

This code outputs the values for Lux and UV intensity in the Serial Monitor

#include <SPI.h>
#include <LTR329.h>
#include <Wire.h>
#include <VEML6070.h>

bool lightsensortype = 0; //0 for tsl - 1 for ltr
//settings for LTR sensor
LTR329 LTR;
unsigned char gain = 1;
unsigned char integrationTime = 0;
unsigned char measurementRate = 3;
VEML6070 veml;


int read_reg(byte address, uint8_t reg)
  {
    int i = 0;
    Wire.beginTransmission(address);
    Wire.write(reg);
    Wire.endTransmission();
    Wire.requestFrom((uint8_t)address, (uint8_t)1);
    delay(1);
    if(Wire.available())
      i = Wire.read();
    return i;
  }


void write_reg(byte address, uint8_t reg, uint8_t val)
  {
    Wire.beginTransmission(address);
    Wire.write(reg);
    Wire.write(val);
    Wire.endTransmission();
  }

void Lightsensor_begin()
  {
    Wire.begin();
    unsigned int u = 0;
    u = read_reg(0x29, 0x80 | 0x0A); //id register
    if ((u & 0xF0) == 0xA0)            // TSL45315
      {
        write_reg(0x29, 0x80 | 0x00, 0x03); //control: power on
        write_reg(0x29, 0x80 | 0x01, 0x02); //config: M=4 T=100ms
        delay(120);
        lightsensortype = 0; //TSL45315
      }
    else
      {
        LTR.begin();
        LTR.setControl(gain, false, false);
        LTR.setMeasurementRate(integrationTime, measurementRate);
        LTR.setPowerUp(); //power on with default settings
        delay(10); //Wait 10 ms (max) - wakeup time from standby
        lightsensortype = 1;                     //
      }
  }


unsigned int Lightsensor_getIlluminance()
  {
    unsigned int lux = 0;
    if (lightsensortype == 0) // TSL45315
    {
      unsigned int u = (read_reg(0x29, 0x80 | 0x04) << 0);  //data low
      u |= (read_reg(0x29, 0x80 | 0x05) << 8); //data high
      lux = u * 4; // calc lux with M=4 and T=100ms
    }
    else if (lightsensortype == 1) //LTR-329ALS-01
    {
      delay(100);
      unsigned int data0, data1;
      for (int i = 0; i < 5; i++) {
        if (LTR.getData(data0, data1)) {
          if(LTR.getLux(gain, integrationTime, data0, data1, lux));
          if(lux > 0) break;
          else delay(10);
        }
        else {
        byte error = LTR.getError();
      }
    }
  }
  return lux;
  }


void setup() {
    Serial.begin(9600);
    Lightsensor_begin();
    veml.begin();

}

void loop() {
    Serial.print("Illuminance: ");
    Serial.println(ightsensor_getIlluminance());
    Serial.print("UV-Intensity: ");
    Serial.println(veml.getUV());
}

Programming (Blockly)​

In Blockly, the sensor can be read using the following block:

In the block, you can select between the different parameters of the brightness/UV sensor:

  • Brightness in LUX
  • UV exposure in µW/cm^2

Projects​

Extras​