A color sensor is a type of sensor which has a property to analyze different types of colors such as green, blue or red, etc. The TCS230/TCS3200 sensor uses a light source for analyzing the color. This means that at first, it emits the light through the LED’s source and then absorbs this light which comes back after the collision of any specific object or thing. On the basis of this reflected light, the Arduino connected with the sensor analyses the color of that specific object.
Typically, the color we perceive in an object is the result of its surface absorbing certain components of the white light that shines upon it, while reflecting other color components that interact with our eyes. White light is a combination of diverse frequencies of visible light, essentially containing a spectrum of colors. In accordance with the three primary colors theory, different colors are created by blending varying proportions of the primary colors: red, green, and blue.
To enable color recognition, a simplified approach involves using three photoelectric diodes, each equipped with modified red, green, and blue filters, and processing their output signals. The TCS3200, on the other hand, streamlines this process by directly outputting digital signals, eliminating the need for a more complex setup.
The TCS3200 color sensor from TAOS is a small device that combines a sensor chip with four white LED lights in an 8-pin SOIC surface mount package. The chip has 64 photodiodes, divided into four groups: 16 for red, 16 for green, 16 for blue, and 16 without filters to capture all light. These diodes are arranged in a grid, with the same-colored ones connected in parallel.
Each 16 photodiodes are connected in parallel, so using the two control pins S2 and S3 we can select which of them will be read. So for example, if we want to detect red color, we can just use the 16 red filtered photodiodes by setting the two pins to low logic level according to the table.
The sensor has two more control pins, S0 and S1 which are used for scaling the output frequency. The frequency can be scaled to three different preset values of 100 %, 20 % or 2%. This frequency-scaling function allows the output of the sensor to be optimized for various frequency counters or microcontrollers.
When a color filter is chosen, the TCS3200 permits only a specific primary color to pass through while obstructing the others. It then measures the intensity of the allowed light. Likewise, the TCS3200 can measure the intensities of red, green, and blue light separately. By analyzing these three light intensity values, the TCS3200D sensor can determine the color of the reflected light.
As shown of the graph,TCS230 Color Sensing Module consists of 8 pins including S0, S1, S2, S3, Output Enable pin, Ground pin, VCC, and output pin.