Skip to main content

29. Sensing the colour of light using photoresistor

Hello friends!

Today I will teach you how to make your Arduino microcontroller sense the colour of light shown on the LDR. Let me give you a glimpse of this project.




As you may have studied in Physics, the intensity of light is inversely proportional to the square of the distance from light source. The intensity of light affects the output voltage of the LDR (or
photoresistor). For this reason, all the LEDs were held at the same distance away from the surface of the LDR to make this project fair. First, the analog values produced by the LDR for each colour were measured with a delay period of 5 seconds. I collected 30 readings for each colour to improve the accuracy. Then I calculated the range and used them in this project's sketch. 
Now, let me explain you how this project works. When the Blue light is shone on the LDR's surface, the intensity of light falls within my calculated range and the Blue LED lights up. The OLED display shows you the colour of the light shone on the LDR's surface and the analog value produced by the photoresistor.

Supplies

  • Arduino Nano
  • Type A to mini B USB cable
  • Solderless Breadboard
  • 0.96" OLED display module - featuring 128 x 64 pixels
  • Photoresistor module
  • 3.3 V lithium battery
  • LEDs (x8) - 2 of each Blue, Yellow, Green and Red
  • Resistors (x4) - 220 Ω
  • Male-to-male jumper wires (x21) - 10 cm
  • 3 pin Female-to-female jumper wires (x3) - 70 cm

Setup

Your setup must look somewhat similar to the one in the image above.

Connections


Photoresistor
  • (+) - 5V
  • (-) - Ground (GND)
  • S - A0
OLED display module
  • GND - Ground
  • VCC - 5V
  • D0 - D10
  • D1 - D9
  • RES (Reset) - D13
  • DC - D11
  • CS - D12
LEDs
  • Cathode (-) - Ground (GND)
  • Blue - D3
  • Yellow - D4
  • Green - D5
  • Red - D6

Coding

For this project, you will be needing the U8glib by Oliver. If you are unsure about the how to use and code for the OLED display module, please refer to https://github.com/olikraus/u8glib. Refer to the examples from this library, for example: Hello World, to learn how to print something on the OLED display module. 
State a variable and assign it to 'analogRead (A0)'. I have used the 'if...else' and 'else if' functions to perform the task for my project. As I have already stated in the first section of this project, calculate the ranges of analog values produced for each colour and record them. Implement them as the parameters of the 'if...else' and 'else if' functions to make each LED light up. The Red LED must light up when the variable's value falls within the assigned range. The similar process must occur for the other LEDs.
If you still need help with the codings, please feel free to comment below or send an email to arduinoprojectsbyr@gmail.com

Final Look

If you have any questions, or suggestions, about this project, please feel free to comment below or send an email to arduinoprojectsbyr@gmail.com.

Comments

Popular posts from this blog

51. Buzz wire game using Arduino

Hello everyone! This is my first Arduino project in 2020 and it is going to be a fun and simple project. You would have heard of the Buzz Wire, a steady hand game, and today you will be learning to make one using Arduino. Hardware components used in this project Arduino Nano USB Type A to mini B cable (for Arduino Nano) Solderless Breadboard - Mini and Full-size LEDs (x2) - Green and Red Resistors (x2) - 220 Ω  Active Buzzer module (KY-012) LCD display module with I2C interface - 16x2 Male-to-Male Jumper wires (x4) - 10cm Female-to-Male Jumper wires (x5) - 20 cm Jumpers (x5) - to reduce the usage of wires Copper wire  Tape (or any form of insulation)  Setup Your hardware setup must look somewhat similar to the ones in the images above. The beginning and end of the copper wire maze must be taped to prevent conductivity between the wire loop and maze. Connections LCD display module with I2C interface GND - Ground VCC - 5V SDA -...

70. Arduino Stopwatch and Timer

Hello everyone! Today I am going to explain you about making an Arduino Stopwatch and Timer, which can be used for time based projects. Read on further to learn more about this project. Hardware components used in this project Arduino Uno USB Type A/ B cable Solderless Breadboard - Full+ LCD display module with I2C interface - 16x2 Potentiometer - 10K Push-buttons (x5) Active Buzzer module (KY-012) LED - Red Resistors (x6) - 10kΩ (x5) and 220Ω (x1) Male-to-Male Jumper wires - 10cm and 20cm Jumpers - to reduce the usage of wires Hardware setup Connections 10K Potentiometer S - A0 (+) - 5V (-) - Ground (GND) Active Buzzer module S - D7 (+) - 5V (-) - Ground (GND) 16x2 LCD display module with I2C interface GND - Ground VCC - 5V SDA - A4 SCL - A5 Push-buttons (+) - 5V (-) - Ground (GND) S - D2, D3, D4, D5, D6 Coding Now, I will explain you about how this real-time project works and you can figure out the coding by this idea.  Push-buttons and their functions D2 - Set Countdown timer D3...

85. Analog and Digital Clock on Adafruit TFT Display using Arduino

 Hey everyone, Sorry I have not posted in a while. Today, I will be presenting you my Analog and Digital Clock on Adafruit TFT Display using Arduino. You can find the schematic and code explanation within this post. Read on further to learn how I did this project. Hardware components used in this project Arduino Mega 2560 Adafruit 2.8" TFT Touch Shield for Arduino w/ Capacitive Touch - You could also use any other Arduino compatible TFT display DS1307 RTC Module Solderless Breadboard - Half+ (This is optional if you are connecting the RTC module to the development board directly) Jumper wires (x4) - Male/Male jumper wires if using solderless breadboard. Female/Male if connecting RTC module directly to Arduino Mega. Software apps Arduino IDE - latest version is recommended Setup Connections DS1307 RTC Module SCL - A5 SDA - A4 VCC - 5V GND - Ground Adafruit TFT Touch shield You can simply place the Adafruit TFT Touch shield onto your Arduino Mega 2560 development board. Make sure to...