Instituto Superior Tecnologico Publico
"JOSE PARDO"
the photocell AND ONE OF ITS APPLICATIONS
CAREER OF: ELECTRONIC
MARK RUIZ Yupari
Student - Researcher
ABDEL ROJAS SANTILLAN
Professor - Advisory
LIMA - PERU 2005
My mother and friends who supported me
FOREWORD
Electronics is the field of engineering and applied physics for the design and implementation of devices, usually electronic circuits, whose operation depends on the flow of electrons to the generation, transmission, reception and storage. This information may be voice or music (voice signals) in a radio receiver, an image on a television screen, or numbers or other data in a computer or computer.
Electronic circuits provide different functions to process this information, including amplification of weak signals to a usable level, the radio wave generation, extraction of information, such as the recovery of the sound signal of a radio wave (demodulation), the control, as in the case of superimposing a sound signal to radio waves (modulation), and logical operations, such as electronic processes taking place on computers.
can also be used for other applications such as measurement of mechanical parameters, thermal, electrical and chemical, these are conducted using devices called sensors and transducers. The sensor is sensitive to changes in the measured variable, as temperature, position, or a chemical concentration. The transducer converts these measurements into electrical signals that can feed reading tools, recording or control of the measured variables. Sensors and transducers can operate in locations away from the observer, and in environments unsuitable or impractical for humans.
Some devices act simultaneously as a sensor and transducer. A thermocouple consists of two junctions of dissimilar metals that generate a small voltage which depends on the thermal difference between the joints. The thermistor is a special resistor whose resistance varies with temperature. A variable resistor can convert the mechanical motion into electrical signal. Used to measure distances capacitors specially designed to detect light and are used photocells.
photoelectric counter counts the number of times an opaque object interposed between a light beam and an optical sensor. The account status is displayed in three seven-segment displays, allowing the online account up to 999 objects.
Yupari Ruiz, Mark
INTRODUCTION
The photocell electronic component based on the photoelectric effect. In its simplest form, consists of an anode and a cathode coated with a photosensitive material. The light striking the cathode releases electrons which are attracted to the anode, positively charged, creating a current flow proportional to the intensity of radiation. The photocells may be empty or filled with an inert gas at low pressure for greater sensitivity. A variant of the photocell, the multiplier or photomultiplier phototube consists of a series of metal plates arranged so that the photoelectric emission is amplified by secondary electrical issue. The multiplier phototube is able to detect extremely faint radiation, making it an essential tool in the area of \u200b\u200bnuclear research.
The photocells are used in burglar alarms, traffic lights and automatic doors. A photocell and a light beam (which can be infrared or invisible to the naked eye) are an essential part of this type of circuit. The light produced by a bulb at one end of the circuit falls on the cell, located at a distance. The track jumps to cut the light beam, causing the closure of a relay and activates the anti-theft or other circuits. Using several types of photocells in the sound recording, television and scintillation counters. Also used in exposure meters.
the photocell AND ONE OF ITS APPLICATIONS
1.1 .- Presentation of the Problem:
The photocell is primarily responsible for the operation of a photoelectric counter.
1.2 .- Formulation of the Problem: How does
the photocell in the operation of a photoelectric counter?
1.3 .- General and Specific Objectives:
Goals: Develop a counter photoelectric
to understand how it works and the role it plays in the device.
Specific Objectives:
1) Obtaining information for the development of a photoelectric counter.
2) Collection of materials (integrated, photocells, resistors, etc.).
3) Collection of tools (soldering iron, solder paste, etc.).
Importance of Research Conduct a study of characteristics and applications of a photocell can help a lot in electronics career.
addition to assembling a photoelectric counter can better understand the operation of the photocell and the role it plays in the device. Join
and understand the operation of various electronic devices can help as a sort of practice that help the student or researcher familiar with the elements to be used in the course of his career.
CHAPTER I
The photocell
1.1 .- DEFINITION:
electronic component based on the photoelectric effect. It consists of an anode and a cathode coated with a photosensitive material. DESCRIPTION
1.2 .- DEFINITION OF:
A) The light striking the cathode releases electrons which are attracted to the anode, positively charged, creating a current flow proportional to the intensity of radiation.
B) The photocells may be empty or filled with an inert gas at low pressure for greater sensitivity.
C) A variant of the photocell, the multiplier phototube or photomultiplier consists of a series of metal plates arranged so that the photoelectric emission is amplified by a secondary electrical issue.
1.3 .- HISTORY OF THE ISSUE:
The introduction of vacuum tubes in the early XX led to the rapid growth of modern electronics. These devices made possible the manipulation of signals, which could not be done in the old telegraph and telephone circuits, or with the early spark transmitters used high voltage to generate radio waves.
For example, vacuum tubes were able to amplify the radio signals and weak sound, and also potentially overlapping audio signals to radio waves. The development of a wide variety of
tubes, designed for specialized functions, enabled the rapid development of radio communications technology before the Second World War and development of early computers, during the war and shortly thereafter.
Today, the transistor, invented in 1948, has almost completely replaced the vacuum tube in most applications. By incorporating a set of semiconductor materials and electrical contacts, the transistor allows the same functions as the vacuum tube, but at a cost, weight and lower power and higher reliability.
subsequent progress in semiconductor technology, attributable in part to the intensity of research associated with space exploration initiative led to the development, in the 1970's, the integrated circuit. These devices may contain hundreds of thousands of transistors on a small piece of material, allowing the construction of complex electronic circuits such as microcomputers or microcomputers, audio and video equipment, and communications satellites.
CHAPTER II
PHOTOELECTRIC COUNTER
2.1 .- Definition:
2.1.1. What it does
photoelectric counter that you plan to join is a circuit that counts the number of times an opaque object stands a beam of light and an optical sensor.
2.1.2. What materials used to perform its function?
uses a sensor, which in our case is a resistance LDR (light dependent resistor) or beam. The light may come from a natural source (sun) or artificial (incandescent, fluorescent, neon, etc.).
2.2 .- Advantages:
2.2.1. Facilities
not use moving parts and is extremely compact, thanks to the adoption of a digital technique called time division multiplex. With no physical contact between the sensor and the external world, the system guarantees the absence of mechanical wear and allows for objects of any kind, no matter their shape or weight
2.2.2. Utility
photoelectric counters used in a wide variety of applications, domestic and industrial, and replace the conventional electromechanical meters. Can be used to count people, animals and objects such as leaves, bottles, cans, boxes, bags, etc.
CONCLUSIONS 1) The photocells have many uses we see everyday such as burglar alarms, traffic lights and automatic doors.
2) Despite being very simple, the transfer principle electron is very useful, only in the photocell is applied through the effect of light on a cathode that is coated with a photosensitive material and release electrons which are transferred to the anode.
3) The photocell is one of the key elements necessary for the proper functioning of a photoelectric counter.
4) The advance of technology over time led to the discovery of new devices such as the photocell and now help man in many ways, whether in security matters (alarms) or production (photoelectric counters).
BIBLIOGRAPHY
- Reference Library Microsoft Encarta
© 1993-2003 Microsoft Corporation. All rights reserved.
- http://Wikipedia.com
- http://comunidadelectronicos.com
- EIGER Educational NGO. "Electronic Components & Devices"
INDEX PAGE I
DEDICATION II
INTRODUCTION FOREWORD III V
The photocell and its Applications 1
1.1 .- Introduction 1.2 .-
Problem 1 Problem Formulation 1
1.3 .- General and specific objectives 1
1.4 .- Importance of 2
research
CHAPTER I 3
the photocell
Definition 3
2.1 .- 2.2 .- 2.3 .- Description 3
History
item 3 CHAPTER II 5
PHOTOELECTRIC COUNTER
3.1 .- Definition 5
3.1.1. What it does 5
3.1.2. What materials used to perform its function? 5
5
3.2 .- Advantages 3.2.1. 5
Facilities 3.2.2. Utility 5 CONCLUSIONS 6
BIBLIOGRAPHY 7
