Optical Detector Definitions of Characteristics 3-dB Bandwidth The frequency where the photodetector ’s output electrical power has dropped 3 dB from a low-frequency reference. The use of these elements and devices is not limited to measuring systems. The sensor acts as a variable resistance that will change status : the resistance increases when the sensor is wet and the resistance is lower when the sensor is dry. For optical sensors to work effectively, they must be the correct type for the application, so that they maintain their sensitivity to the property they measure. A. There are three regions in this type of diode. At the base-emitter junctions of a transistor, one finds …………… 1. a reverse bias 2. a wide dep... Microwave Frequency Bands The microwave spectrum is usually defined as a range of frequencies ranging from 1 GH... Oscillators Objective Questions: Q 1. The transmissive sensor is used in most applications for small distances and narrow objects. These are also used in the systems which perform specific tasks, to communicate with the real world. This article discusses the types of flame detectors on the market. It is the ability of the sensor to indicate the same output over a period of time for a constant input. A. Once you have completed the questions, click on the 'Submit Answers for Grading' button at the bottom of this page to get your results. Top Bio Instrumentation Objective Questions, Important Objective Questions On Productivity, Instrumentation and Control Engineering Objective Test 2, Instrumentation and Control Engineering Objective Test 1. When a PN Junction is formed, diffusion current causes 1) mixing of current carriers 2) ... Control System_2 Objective Questions: Que 1. Resistance temperature detectors B. Thermistors C. Ultrasonic D. All of these View Answer / Hide Answer. The detectors used in optical sensors is - Published on 16 Sep 15. a. Optical heterodyne detection is a method of extracting information encoded as modulation of the phase, frequency or both of electromagnetic radiation in the wavelength band of visible or infrared light. An optical detector is a device that converts light signals into electrical signals, which can then be amplified and processed. The decibel is a measure of 1. Current 2. It is sensitive to LPG, Hydrogen, Smoke, Methane, Propane, Alcohol, Butane and other industrial combustible gases. (Quadrant 1 is when the operating voltage and current are both positive.) Home >> Category >> Electrical Engineering (MCQ) questions and answers >> Electrical and Electronic Measurements & Instrumentation; Q. The sensor is integrated with a diaphragm and a set of resistors on integrated chips so that pressure is detected as a change in resistance. Design Procedures For Optical Sensor Circuits First, obtain values of RE and RL. TMD4903 : Color, ALS, and proximity sensor module with mobeam™ and universal remote control. To use the LED as an optical detector, do not forward bias the LED into quadrant #1 of the current-voltage (I-V) curve. Lowest. 3-The sensors are classified on the basis of. Light-to-Frequency (LTF) sensors convert measurements of light intensity to a digital form for direct interfacing to a microcontroller. Q8. 15. They are Active sensors and passive sensors. Two-Port Network Parameters - Electronic Engineering (MCQ) questions & answers Home >> Category >> Electronic Engineering (MCQ) questions & answers >> Two-Port Network Parameters 1) Which among the following represents the precise condition of reciprocity for transmission parameters? Light emitting diode. As mentioned every objest acts as transmitter as they emit infrared light. This technology was invented in the latest of 1950’s. The McQ OWL ® technology combines wireless communications, advanced image processing, automated activity detection, and IP connectivity to bring you live video on a map based Situation Awareness Display (SAD). The main classes are Photo resistors, photo voltaic and photo emitters. It consists of special optical and electronic devices, which integrates adaptive algorithm for indoor and outdoor application environment. 17. The direct photo-electron interaction is very rapid so these detectors have the potential of following fast changing radiation levels. Acts as a fixed resistance. In the growth market of sensor systems, First Sensor develops and produces standard products and customer-specific solutions for the ever-increasing number of applications in the industrial, medical, and mobility target markets. : The McQ RANGER ® is a low cost sensor system using seismic, acoustic and magnetic to detect people, vehicles and aircraft. Mechanical device can act as a primary transducer. Photo diode. Whether the signal from sensor A leads sensor B or vice versa defines the direction of relative motion. The absorbed photons make electron–hole pairs in the depletion region. Optical sensors measure changes to the amount of light shining on the sensor. A second light detector is added 90° out of phase. A. Dubai Sensors is an e-commerce platform, where we host an array of industrial products, ranging from sensors to controllers, measuring equipment to accessories, Dubai Sensor is the place where we provide to our kind customers with all the industrial and automation solutions they desire. D. Low View Answer. A.C. power into D.C. power     2. This facilitates coupling the LED light with an optical device. This relates to a displacement of half a scale line. Proximity Sensor Features. Oriel Instruments. Sensors are low, and go high when they see a white surface. The white side of the Which of the following is not covered under Mechanical energy domain? Following type of sensors are used to generate information in object grasping and obstacle avoidance. 7-It is the ability of the sensor to indicate the same output over a period of time for a constant input. A. A Sensor converts the physical parameter (for example: temperature, blood pressure, humidity, speed, etc.) IR gas sensing technology provides for fail-to-safe operation in contrast to electrocatalytic sensors since optical sensing is an active technology, which continuously monitors for sensor faults and communicates them to the user. Optical sensors are integral parts of many common devices, including computers, copy machines (xerox) and light fixtures that turn on automatically in the dark. For example the voltage of a temperature sensor changes by 1mV for every 1 o C change … w.wang Types of Optical Detectors Photon detectors may be further subdivided according to the physical effect that produces the detector response. An oscillator converts ……………..     1. 12, Villach, Austria - (Marcus.Baumgart, Cristina.Consani)@ctr.at 2 Infineon Technologies Austria AG, Development Center Graz, Babenberger Str. :: What Is an Photodetector? current/voltage characteristics is shown in the following figure: (a) Photovoltaic Operation -Rl>>Rd, load line (b) Zero Bias Operation -Rl<