Transducers (Light and Chemical) PDF

Transducers Light/Electromagnetic Transducers Photovoltaic/Solar Cell Photodiode/Phototransistor LDR (Light Dependent Resistor) LASER PIR (Passive Infrared) Sensor Hall Effect Sensor Ultrasonic Sensor Magnetometer Color Sensor Proximity Sensors (various types...

Transducers Light/Electromagnetic Transducers Photovoltaic/Solar Cell Photodiode/Phototransistor LDR (Light Dependent Resistor) LASER PIR (Passive Infrared) Sensor Hall Effect Sensor Ultrasonic Sensor Magnetometer Color Sensor Proximity Sensors (various types) RF Diode Photovoltaic Cell (Solar Cell) semiconductor device that converts the light into electrical energy The name Photovoltaic is because of their voltage producing capability from light Its role in sustainable energy is to reduce the carbon footprint by harnessing solar energy Photovoltaic Cell (Solar Cell) How light energy is converted into electrical energy Photovoltaic Effect is a way which light energy is converted into electrical energy Sunlight photons knock electrons loose from atoms. Electrons flow through the cell, generating electricity. Photovoltaic Cell (Solar Cell) Applications: Solar Panels in residential rooftops reducing electricity bills. Solar-Powered Chargers for device charging on the go Solar street lighting that is cost-efficient Photodiode a semiconductor device with a P-N junction that converts photons (or light) into electrical current. has a similar structure as a normal PN junction diode except for a light-sensitive exposed junction. can be used in both forward and reverse bias. produces both voltage and current. mainly used in solar cells to power electrical equipment from solar energy. Phototransistor a light-sensitive transistor that is used to amplify the photoelectric current generated from converting light energy has two or three terminals depending on its design has a similar structure to a transistor except it has a light-sensitive base region. connected only in forward bias requires a power source to operate generates current only mainly used for detecting or sensing light intensity LDR (Light Dependent Resistor) tiny light-sensing devices also known as photoresistors resistor whose resistance changes as the amount of light falling on it changes. works on the principle of photoconductivity whenever the light falls on its photoconductive material Laser an acronym for “light amplification by stimulated emission of radiation.” a special type of diode specifically designed to convert electrical energy into light through a process called stimulated emission functions similarly to a regular p-n junction but is optimized for light generation Unlike LEDs, which emit light in various directions, laser diodes produce a concentrated, coherent light beam The color of the laser light depends on the type of semiconductor material used with different materials emitting different wavelengths of light. PIR (Passive Infrared) Sensor an electronic sensor used in motion detectors triggered lighting devices and protection systems that measure devices emitting infrared light in their field of view useful for detecting the presence of people or animals through the heat emitted by their bodies commonly utilized in security alarms and automatic lighting applications. Hall Effect Sensor transducer that varies its output voltage in response to a magnetic field. used for proximity switching, positioning, speed detection, and current sensing applications. Hall Effect Sensor use a thin semiconductor with a continuous current. When exposed to a magnetic field, this field deflects charge carriers (electrons and holes) to the sides of the semiconductor. This deflection creates a Hall voltage perpendicular to the current flow and the magnetic field The Hall voltage varies with the magnetic field's polarity and intensity, allowing the sensor to detect and measure the magnetic field effectively. Ultrasonic Sensor electronic device that measures the distance of a target object by emitting ultrasonic sound waves converts the reflected sound into an electrical signal work by sending out a sound wave at a frequency above the range of human hearing The transducer of the sensor acts as a microphone to receive and send the ultrasonic sound Ultrasonic sensors, like many others, use a single transducer to send a pulse and to receive the echo. the sensor determines the distance to a target by measuring time lapses between the sending and receiving of the ultrasonic pulse. Magnetometer device that measures magnetic field or magnetic dipole moment Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. Magnetometers specifically used to measure the Earth’s field are of two types: absolute and relative (classed by their methods of calibration). Absolute magnetometers - are calibrated with reference to their own known internal constants. Relative magnetometers - must be calibrated by reference to a known, accurately measured magnetic field. Color Sensor uses photodiodes to convert light reflected from an object into electrical signals these signals are then processed to determine the object's color based on its light absorption properties selectively detect light within the visible spectrum to differentiate colors it relies on color models (RGB, CMYK) to translate light information into color data. Proximity Sensor a non-contact sensor that detects the presence of an object (often referred to as the “target”) when the target enters the sensor’s field depending on the type of proximity sensor, sound, light, infrared radiation (IR), or electromagnetic fields may be utilized by the sensor to detect a target used in phones, recycling plants, self-driving cars, anti-aircraft systems, and assembly lines Proximity Sensor Inductive Proximity Sensor useful to detect the metallic object which is present next to their active side this sensor operate under the electrical principal of inductance; where a fluctuating current induces an electromotive force(EMF) in a target object Optical Proximity Sensor includes a light source, and a sensor that detects the light These sensors detect objects directly in front of them by the detecting the sensor’s own transmitted light reflected back from an object’s surface Proximity Sensor Capacitive Proximity Sensor can detect both metallic and non-metallic targets in powder, granulate, liquid, and solid form use the variance in the capacitance of the sensor to concluded that an object has been detected Magnetic Proximity Sensor this sensor only detects the magnetic field sense the presence of a magnetic object the target, characterized by its magnetic field, triggers the switching process; when it enters the detection range of the sensor. RF Diode specialized components engineered to manage high-power radio frequency (RF) signals within a range of electronic devices such as stereo amplifiers, radio transmitters, television monitors, and various RF or microwave applications crucial for efficiently controlling and manipulating RF signals, ensuring optimal performance and signal integrity in communication systems and electronic equipment designed to handle high-frequency signals efficiently Chemical Transducers Gas Sensor (Any type) Soil Moisture Sensor Humidity/Hygrometer Turbidity Sensor Salinity Sensor pH Sensor Fuel Cell E-nose (Electronic Nose) Heartbeat Sensor Breathalyzer Chemical Transducers Chemical transducers are essential tools that transform chemical information into signals that can be measured, enabling the detection and measurement of a variety of compounds in a broad range of applications. In industries including food safety, industrial process control, medical diagnostics, and environmental monitoring, these transducers are essential. Gas Sensors a device which detects the presence or concentration of gases in the atmosphere Electromechanical Gas Sensor an electrochemical cell consisting of a sensing electrode, a reference electrode, and a counter electrode separated by a thin layer of electrolyte. a device that quantitatively detects a particular chemical species as an oxidation or reduction current. Soil Moisture Sensor measure the volumetric water content in the soil. sensor mainly utilizes capacitance to gauge the water content of the soil The sensor interacts with the water molecules in the soil and changes its capacitance value depending on the amount of water Humidity Sensor / Hygrometer sensitive electronic devices used to measure the air's humidity divided into two categories: relative humidity sensors and absolute humidity sensors Capacitive Humidity Sensor the sensing element of a capacitive sensor is a capacitor. Here, the relative humidity values are determined by measuring the dielectric material's change in electrical permittivity. Resistive Humidity Sensor Humidity changes are detected by measuring changes in this material's resistivity value. Turbidity Sensor used to quantify the amount of total dissolved/suspended solids in a solution as well as its cloudiness or haziness for determining the particle concentration and purity of a solution, such as water Turbidity is the measure of relative clarity of a liquid. It is an optical characteristic of water and is a measurement of the amount of light that is scattered by material in the water when a light is shined through the water sample. The higher the intensity of scattered light, the higher the turbidity. Salinity Sensor used to determine the concentration or refractive index of saline solution by weight measures the conductivity of a solution with a high ion concentration Salinity refers to the total amount of all non-carbonate salts dissolved in water it is typically expressed in parts per thousand (1 ppt = 1000 mg/L) and is particularly important in seawater Salinity Sensor Electrode type salinity sensor operates by immersing two electrodes in the solution whose salinity is to be measured. When an electrical voltage is applied across the electrodes, ions in the solution conduct electricity, causing a measurable current to flow. The sensor measures this current and converts it into a salinity value, typically using a calibration curve that relates conductivity to salinity. Induction type salinity sensor uses a magnetic field to induce a current in the solution and measures the resulting voltage to determine the salinity pH Sensor device used to measure the acidity or alkalinity of a solution it is widely used in various industries, including water treatment, food and beverage production, agriculture, and scientific research the sensor typically comprises a pH-sensitive electrode and a reference electrode measures electric potential using two electrodes inserted into the liquid to create an electrical circuit one electrode, called the reference electrode, contains a substance with a known electric potential the other electrode, known as the sensor electrode, is inserted into the solution being tested the electric potential is determined by comparing the reference electrode to the sensor electrode. Fuel Cell a device that converts chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied. E-Nose (Electronic Nose) a sensor device that detects smell more effectively than the human smell It is used to distinguish complex volatiles that reproduce the structure and principle of olfactory sense It is mainly used for quality evaluation, maturity detection, and species identification in fruit and vegetable testing Heartbeat Sensor device designed to monitor and measure heart rate in real-time commonly used in various applications such as fitness tracking, medical monitoring, and research the sensor detects the pulse by measuring changes in blood volume through the skin using optical or electrical methods Heartbeat Sensor The most common type of heartbeat sensor uses an optical method to measure the heart rate. This method involves a light-emitting diode (LED) and a photodetector. The LED emits light that penetrates the skin, and the photodetector measures the amount of light that is reflected or absorbed by the blood flowing through the veins. As the heart pumps blood, the volume of blood changes, leading to variations in the light absorption. These variations are detected and processed to calculate the heart rate. Breathalyzer operate on the principle that alcohol present in the bloodstream is exhaled in the breath When a person breathes into the device, it measures the amount of alcohol vapor present. There are three main types of technologies used in breathalyzers: Fuel Cell Sensors Semiconductor Oxide Sensors Infrared Spectroscopy Breathalyzer Fuel Cell Breathalyzers relies on principles of electrochemistry, particularly oxidation-reduction reactions. the oxidation of ethanol to acetic acid, which produces electrons that generate an electric current measured by the device. Semiconductor Oxide Sensors based on the change in electrical resistance caused by the interaction between ethanol and the sensor material Infrared spectroscopy based on the Beer-Lambert law relates the absorption of light to the properties of the material through which the light is traveling It helps in quantifying the concentration of alcohol in the breath sample by measuring the absorbed infrared radiation