Digital Distance Sensor with Pololu Carrier – 0.5 cm to 5 cm by Sharp

Senses an object between 0.5 and 5 centimeters away that comes with a low current draw and on a tiny carrier board with all of the external components required to make it work. There is also another sensor that detects objects that are 2 to 10cm away as well.

Technical Description

With its quick response time, small size, low current draw, and short minimum sensing distance, this sensor is a good choice for non-contact, close-proximity object detection.

Limitation

Sensor is close range distance sensor and it will only tell you if there is an object within the detection range along their narrow lines of sight; they will not tell you how far away the object is.

Skill

Rookie

Sample Sensors

Digital Distance Sensor: https://www.adafruit.com/product/3025

Sample Exercise

https://www.instructables.com/id/FPiDroid-House-beta/  (Advanced Smart House Build)

Analog Light Sensor Breakout from Adafruit

Analog light sensor that is a great to upgrade a project that uses a photocell and needs RoHS compliance. Due to the high rejection ratio of infrared radiation, the spectral response of the ambient light sensor is close to that of human eyes.

Technical Description

connect – to ground, + to 2.5V-5.5V or so to power it. Measure the analog voltage on the OUT pin. That’s it! The voltage will increase when the sensor detects more light.

Limitation

Simple sensor that can only detect ambient light that are on par with human eyes

Skill

Easy

Sample Sensors

Analog Light Sensor: https://www.sparkfun.com/products/13959. 

Sample Exercise

Luminosity Sensor from Adafruit

An advanced digital light sensor, ideal for use in a wide range of light situations. 

Technical Description

Compared to low cost CdS cells, this sensor is more precise, allowing for exact Lux calculations and can be configured for different gain/timing ranges to detect light ranges from up to 0.1 – 40,000+ Lux on the fly. The  sensor contains both infrared and full spectrum diodes, which means you can separately measure infrared, full-spectrum or human-visible light. Most sensors can only detect one or the other, which does not accurately represent what human eyes see

Limitations

Although very practical for everyday measure, it is not highly accurate sensor. Also with too much or too little light, sensors will either saturate or will need to increase integration time

Skills

Rookie

Sample Sensor

https://www.adafruit.com/product/439

Sample Exercise

https://learn.adafruit.com/tsl2561/overview

Photo Transistor Light Sensor from Adafruit

Simple sensor that detects ambient light. It’s kind of the opposite of an LED – when light hits the little chip inside, it induces current to flow from the long pin to the short pin.

Technical Description

The sensor connect the pin connected to the ‘thicker’ part of the sensor to 3-15VDC or so, and the thinner-part pin through a ~1K-10K series resistor to ground. When its dark, there’s almost no current flowing through the sensor or resistor and the analog voltage is near ground. When there’s light near the sensor, the current through the resistor will increase, raising the voltage.

Limitations

Phototransistors that are made of silicon are not capable of handling voltages over 1,000 Volts
Phototransistors are also more vulnerable to surges and spikes of electricity as well as electromagnetic energy.

Skill

Rookie

Sample Sensors

https://www.adafruit.com/product/2831

Sample Exercise

http://bildr.org/?s=photo+transistor