File Photoresistor.svg thumb The symbol for a photoresistor ref British Standard 3939 ref Image LDR.jpg thumb A light dependent resistor Image Streetlight control.jpg thumb The internal components of a photoelectric control for a typical American streetlight . The photoresistor is facing rightwards, and controls whether current flows through the heater which opens the main power contacts. At night, the heater cools, closing the power contacts, energizing the street light. The heater bimetal mechanism provides a built in light level transient filter. A photoresistor or light dependent resistor LDR is a resistor whose electrical resistance resistance decreases with increasing incident light intensity. It can also be referred to as a photoconductor . A photoresistor is made of a high resistance semiconductor . If light falling on the device is of high enough frequency , photon s absorbed by the semiconductor give bound electron s enough energy to jump into the conduction band . The resulting free electron and its electron hole hole partner conduct electricity, thereby lowering Electrical resistance resistance . A photoelectric device can be either intrinsic or extrinsic. An intrinsic semiconductor has its own charge carrier s and is not an efficient semiconductor, e.g. silicon. In intrinsic devices the only available electrons are in the valence band , and hence the photon must have enough energy to excite the electron across the entire bandgap . Extrinsic devices have impurities, also called dopants , added whose ground state energy is closer to the conduction band since the electrons ... nevadabat Moonlight MoonLight.html Using a photoresistor to measure nocturnal light levels The Moonlight Sensor http www.sccs.swarthmore.edu users 06 adem engin e72 lab7 Using a photoresistor to track light http www.acroname.com howto photoresistor photoresistor.html Connecting a photoresistor to a circuit http www.radio electronics.com info data resistor ldr light dependent resistor.php Photoresistor ... more details
oldffdfull date 2009 November 3 Summary This a custom made image of what a photoresistor circuit looks like Licensing PD self date March 2007 ... more details
Image Singing Candle Diagram.svg right thumb A simplified diagram of the singing candle. A singing candle is an electro acoustic installation art installation . The movements of a candle flame are transformed into sound by means of a Photoresistor light dependent resistor LDR . The sound waves, in return, have an influence on the flame, through an amplifier and loudspeaker , forming a feedback loop . DEFAULTSORT Singing Candle Category Acoustics electron stub ... more details
Electro optical sensors are those which convert the light rays in to electronic signal very similar to the photoresistor , these are applied in emergency lamps such that when there is light it is made to switch off and when there is no light it is automatically made to switch on. In aviation , electro optical devices have been used as part of the avionics , in order to expand both range and vision at low ambient light levels. Electronics stub Category Sensors ar ... more details
Unreferenced stub auto yes date December 2009 Image Hawleyite 3D balls.png thumb right Cadmium sulfide In chemistry , metal chalcogenides are chemical compound compounds consisting of a metal and an element which is a member of the chalcogen column of the periodic table . While oxygen is a member of the chalcogens, so all metal oxide s are technically metal chalcogenides, the term is commonly used only to refer to compounds of a metal with sulfur , selenium or tellurium , and polonium . Important metal chalcogenides include the semiconductor cadmium sulfide , which is used in the production of photoresistor s, and cadmium selenide , which is used to produce quantum dots . DEFAULTSORT Metal Chalcogenide Category Inorganic compounds Inorganic compound stub hi ... more details
File Tondi Elektroonika logo.png 200px right Tondi Elektroonika , formerly known as Tallinna Pooljuhttakistite Tehas Tallinn Semiconductor Resistor Factory , Hans P gelmanni nimeline Tallinna Raadiotehnika Tehas Tallinn Radiotechnical Factory named after Hans P gelmann and Hans P gelmanni nimeline Elektrotehnika Tehas Hans P gelmann Electrotechnical Factory , as well as Factory number A 1381 was a factory of electrotechnical components located in Tallinn , Estonia . It was a significant component of the Soviet Military industrial complex . ref cite news first Jaak last Vihmand publisher Postimees url http www.postimees.ee ?id 23974 title Salajased s jaseadmed ja kuulsad kuuldeaparaadid Tondilt date 2008 08 01 accessdate 2008 11 22 et icon ref Production Components The factory has manufactured photoresistor s, varistor s, transistor s, thyristors and Integrated circuit microchip s. From 1959 to 1978, the factory manufactured temperature sensitive photoresistor s 04 AN in Cyrillic 04 for use in Soviet military rocket guidance system s. This brought the factory under the official military industrial complex umbrella, and the factory was assigned a number &mdash A 1381 &mdash and the location reference was removed from the factory s name. Consumer products The factory has manufactured consumer grade battery systems, electric fence systems, car engine diagnostics devices and even souvenir radio set s. Since 1979, an important &mdash and by 2008, the main &mdash line of production has been hearing aid s, peaking in 1989 at 176 500 units manufactured. Recreational activities The mixed choir Helitron was initially set up to cater to employees of Tondi Elektroonika. Current status Currently, AS Tondi Elektroonika manufactures mainly hearing aids. References reflist External links http www.tondi.ee Official website Category Defence companies of the Soviet Union Category Companies of Estonia Category Tallinn Category 1950s establishments in Estonia et Tallinna Pooljuhtt ... more details
A phototube is a type of gas filled tube gas filled or vacuum tube that is extremely sensitive to light in the ultraviolet , visible light visible , and near infrared ranges of the electromagnetic spectrum . ref cite web url http www.accessscience.com content.aspx?id 512000 last Weaver first James title Phototube publisher McGraw Hill accessdate 2009 05 08 ref Operating principles Phototubes operate according to the photoelectric effect Incoming photon s strike a photocathode , generating electron s, which are attracted to an anode . Thus current flow is dependent on the frequency and intensity of incoming photons. Unlike photomultiplier tubes, no amplification takes place, so the current generated is typically on the order of microampere s. ref cite web url http www.du.edu etuttle electron elect30.htm title Electronics 30 Phototubes author J.B. Calvert publisher University of Denver date 2002 01 16 ref Applications One major application of the phototube was the reading of optical Sound film sound tracks for projected films. Phototubes were used in a variety of light sensing applications until they were superseded by photoresistor s and photodiode s. References reflist Category Optical devices Category Sensors Category Vacuum tubes tech stub ar de Photozelle es Fototubo eo Foto elo it Fotocellula hu Fotocella nl Fotocel ja pl Fotokom rka ... more details
Orphan date February 2009 The Age of Silicon is an option in the Physics Higher School Certificate New South Wales Higher School Certificate HSC syllabus defined by the state government education board Board of Studies in New South Wales , Australia . Other physics options are Geophysics, Medical Physics, Astrophysics and From Quanta to Quarks. The content of this option is basically an introduction to electronics. blockquote This module increases students understanding of the applications and uses of physics, the implications of physics for society and the environment, and current issues, research and developments in physics. blockquote ref http www.boardofstudies.nsw.edu.au syllabus hsc pdf doc physics stg6 syl.pdf ref The main topics in this option are Voltage divider Transistor Photoresistor Thermistors Relay Light emitting diode LED Logic gate Operational amplifier . This option is not covered by any school textbook. br http science.uniserve.edu.au school curric stage6 phys silicon Uniserve http quobject.com learningresources physics theageofsilicon TheAgeOfSilicon Summary notes http www.jaconline.com.au physicsnsw downloads Physics HSC NSW.pdf Jacaranda References Reflist added above categories infobox footers by script assisted edit Category Education in New South Wales ... more details
Optical Sorting is a process of visually sorting a product though the use of Photodetector light sensors , Camera ref http www.woodheadpublishing.com en book.aspx?bookID 614&printer yes Detecting foreign bodies in food ref , or the Human eye ref Image Processing for the Food Industry , E. R. Davis World Scientific Publishing Co. Pte. Ltd. London, 2000 ref . In its simplest operation, a machine will simply see how much light is reflected off the object using a simple Photodetector such as a Photoresistor and accept or reject the item depending on how reflective it is light or dark . More sophisticated systems use Image processing to discriminate the colors of the object, often via a controlled Spectrum spectra of light, even beyond the visible spectrum into the IR and UV range. Shape detection is an evolving ability. The common method of removal is jets of compressed air, but others exist. The term Optical sorting also includes manual seeing and manipulating processes. http www.odenberg.com Odenberg Engineering , http www.lasersorter.com Visys , Satake Corporation , http www.bestsorting.com Best , and http www.buhlergroup.com 17217EN.asp Sortex are some companies that build Optical Sorting machines for the food sector to ensure consistent quality & safety. Further reading references optics stub Category Optics stubs Category Optics ... more details
Orphan date February 2011 Image 5008 S.jpg Beaulieu 5008 S with Schneider Kreuznach Optivaron zoom thumb The Beaulieu 5008 S is a Super 8 mm film dual speed professional camera. This camera was released by the Beaulieu company . It was first launched in February 1974. The primary component that set this camera apart from other Super 8mm cameras of the era was it was made with a unique Single lens reflex camera SLR function and interchangeable Schneider Kreuznach and Angenieux zoom lens. Features Format Super 8 Kodapak, Kodachrome or Ektachrome see external link Lens changeable, Schneider Kreuznach Optivaron zoom 6 66 mm f 1.8 link yes or Angenieux 6 80 mm f 1.2 1.4 Macro with Schneider Kreuznach from 0 to 1500 mm just under 5 ft Filter built in Wratten number Wratten filter 85 Aperture motor driven with reflexmatic motor or manual Zooming Electric speed from 4 to 12 seconds or manual Viewer Reflex with tilting matte screen Shutter with guillotine 1 40 sec 18 images or 1 60 sec 24 images Exposure metering photoresistor CdS cell ASA 25 to 400 Remote control electrical Power supply rechargeable 500mA 7.2 V NiCd batt. Sound built in amplifier 50 to 12 kHz 1.5 dB 24 images and 50 to 9.5 kHz 1.5 dB 18 images Signal noise 57 dB Earphone Z 1.5 K Mike DIN 5 pins, with 3 sensibilities 0.15mV to 20mV Z 5K , 3mV to 15mV Z 100K and 30mV to 1.2V Z 500K Capstan instability 0.4 Dimensions 34 cm l x 10 cm w x 21 cm h Weight 2.55 kg with Angenieux zoom 6 80 See also Super 8 mm film Super 8 film cameras References Unreferenced date November 2009 Reflist External links http www.beaulieu.fr Beaulieu France Category Movie cameras Category 1974 introductions ... more details
Infobox camera camera name Canon 7 image name Canon 7 with 50mm f0.95 IMG 0374.JPG type 35 mm rangefinder camera lens mount Leica Camera Leica M39 lens mount M39 Screw Mount with special bayonet mount for 50mm f0.95 lens focus manual exposure manual flash None on the 7 External cold shoe on the 7s frame rate dimensions 140mm x 81mm x 31mm The Canon 7 was a rangefinder camera rangefinder system camera produced by Canon Inc. , the last compatible with the Leica Camera Leica M39 lens mount . It was introduced in September 1961, with an integrated Selenium meter cell. Further versions, branded Canon 7s and Canon 7s Type II or Canon 7sZ , modified the design slightly by introducing a Photoresistor cadmium sulfide cell . The Canon 7 came as the first Canon Single lens reflex camera reflex cameras were already on the market, but it was felt that there was a need for a fast shooting rangefinder camera for reportage. In this niche, the Canon 7 came into direct competition with the Leica M3 . Some Canon 7s were sold in the USA as a Bell & Howell the Canon Bell & Howell partnership lasted until 1975. External links Commonscat Canon 7 http www.antiquecameras.net canonrfcameras.html Canon RF Camera Price & Info Guide http www.cameraquest.com canon7sz.htm Canon 7 7s 7sZ on cameraquest.com http www.photoethnography.com ClassicCameras index frameset.html?Canon7.html mainFrame Canon 7 by Karen Nakamura http www.canon.com camera museum camera film data 1956 1965 1961 7.html?lang us&categ srs&page range&p 1 Canon 7 on Canon Camera Museum http www.butkus.org chinon canon canon 7 canon 7.htm Canon 7 User manual on butkus.org Category Canon cameras ... more details
orphan date May 2008 The AxeSynth is an electronic musical instrument invented by Tony Amendolare of Long Island , N.Y. in the winter of 2004. The first AxeSynths that were produced used the vintage Texas Instruments SN76477 Sound Generator integrated circuit . The SN76477 IC was the sound synthesizer used in the Space Invaders video arcade game of the late 1970s and early 80 s, this fact prompted the AxeSynth to be nicknamed the Atari by some of its noted users. Shaped like a guitar , with a neck and body, it utilizes two sensors as the user interface to produce synthesized tones. The main sensor, located on the neck is a Force Sensitive Resistor FSR similar to a ribbon controller . Linear changes in resistance are produced when the FSR is touched at various positions along its length. This variable electrical resistance is similar to that of a common linear potentiometer and subsequently controls the oscillation of frequencies produced by the main synthesizer IC. The AxeSynth also utilizes a photoresistor sensor, or CdS cell, whereby varying amounts of light received by the sensor is controlled by the musician s hand, resembling Theremin like frequency control. Although not a circuit bent instrument in the strict tradition since it is made from new parts as opposed to recycled circuits, its creation was inspired by the experimental electronic art of Circuit Bending , and particularly the creations of Reed Ghazala . File Axesynth.jpg AxeSynth Articles on the Web br http gizmodo.com 031971 economy of scales spaceaxe and spacesynth AxeSynth SpaceAxe Model on Gizmodo br http www.synthtopia.com news 04 11 Axe Guitar Synth.html Sci Fi Theremin Guitar br http musicthing.blogspot.com 2004 11 strange guitar synth looks like dr who.html MusicThing Doctor Who Prop br http www.youtube.com watch?v UcrqlZ60dgk Chicago Electronic Band Velva Live With Two AxeSynths br http www.youtube.com watch?v TtpdIpHwT9Y YouTube Video of Mutemath Playing The AxeSynth at BluesFest Category Gui ... more details
The Lynx is a family of rangefinder camera s made by Japanese company Yashica from the early 1960s with coupled and fixed photographic lens lenses . Models The Lynx 1000 was introduced in 1960. It has a 1 1.8 45 mm lens with 6 elements in 4 groups. The shutter photography diaphragm shutter is capable of a maximum speed of 1 1000 second, an extra stop faster than most other diaphragm shutters. Light is metered using a small selenium photovoltaic cell behind a lens array, powering a galvanometer . The film speed for the metering system can be set from 10 to 800 ASA. The Lynx 5000 was introduced in 1962. It was an upgrade to the Lynx 1000 and replaced the photovoltaic cell with a cadmium sulfide CdS photoresistor , requiring a mercury battery for the light meter. The Lynx 14 was released in 1965. The lens of the 1000 5000 was replaced by a large 1 1.4 45 mm with 7 elements in 5 groups. In 1968 the Lynx 5000e and Lynx 14e were introduced. These variants both switched to two PX640 batteries instead of a single PX625 in order to drive a more sensitive light sensor with a higher voltage. The galvanometer of the light meter was replaced with two indicator lights, showing when the exposure was over or under . See also Yashica Electro 35 A later series of rangefinders with aperture priority auto exposure External links http www.yashica guy.com document chrono2.html Yashica 35mm Rangefinder Chronology & Specifications II by Yashica Guy http www.photoethnography.com ClassicCameras index frameset.html?YashicaLynx14.html mainFrame Yashica Lynx 14 by Karen Nakamura at Photoethnography.com http pheugo.com cameras index.php?page lynx5000 Yashica Lynx 5000 actually the whole series by Daniel R. Mitchell DEFAULTSORT Lynx Category rangefinder cameras Category 135 film cameras ... more details
image Merker Durchlauferhitzer.jpg thumb right Merker gas fired water heater from the 1930 s, with pilot light clearly visible through the aperture in the front cover. The large opening allowed for the manual lighting of the pilot light by a lit match or taper A pilot light is a small gas flame , usually natural gas or liquefied petroleum gas , which is kept alight in order to serve as an ignition source for a more powerful gas burner. Origin During the American colonial period , people kept a small flame called a pilot burning in order to quickly light a fire for a fireplace or for a cooking stove. fact date May 2009 Uses Common applications include household water heater s, central heating systems, flamethrower s, and hot air balloon s. While most commercial kitchens still rely on pilot lights for burners, ovens, and grills, current residential systems typically use an electrical ignition. More commonly known as standby on modern remote control fires. Safety protection In natural gas furnaces, water heaters, and room heating systems, a safety cut off switch is usually included so that the gas supply to the pilot and heating system is shut off by an electrically operated valve if the pilot light goes out. This cut off switch usually detects the pilot light in one of three ways A sensor there must be a more descriptive word than sensor filled with mercury element mercury is used to detect the heat of the pilot light. Contraction of the mercury results in sufficient pressure to operate an electrical switch that interrupts the flow of electricity and shuts off the gas valve when the pilot light goes out. A photoresistor is used to detect the light from the pilot lamp. When the pilot light goes out, electrical circuit ry connected to the photoresistor shuts off the gas valve. Use of a pilot generator or a thermocouple in the flame provides heating appliance safety as it generates enough electrical current from the burning flame to hold the gas valve open. If the pilot ... more details
distinguish electro optics Optoelectronics is the study and application of electronics electronic devices that source, detect and control light , usually considered a sub field of photonics . In this context, light often includes invisible forms of radiation such as gamma ray s, X ray s, ultraviolet and infrared , in addition to visible light. Optoelectronic devices are electrical to optical or optical to electrical transducer s, or instruments that use such devices in their operation. Electro optics is often erroneously used as a synonym, but is in fact a wider branch of physics that deals with all interactions between light and electric field s, whether or not they form part of an electronic device. Optoelectronics is based on the quantum mechanics quantum mechanical effects of light on semiconductor semiconducting materials, sometimes in the presence of electric field s. ref http www.element 14.com community docs DOC 22516 l physics and technology vishay optoelectronics Physics and Technology Vishay Optoelectronics ref Photoelectric or photovoltaic effect, used in photodiode s including solar cell s phototransistor s photomultiplier s integrated optical circuit IOC elements Photoconductivity , used in photoresistor s photoconductive camera tube s charge coupled imaging device s Stimulated emission , used in injection laser diode s quantum cascade laser s Lossev effect, or radiative recombination , used in light emitting diode s or LED Photoemissivity , used in photoemissive camera tube Important applications ref http www.element 14.com community docs DOC 22930 l optocoupler application examples Optocoupler Application Examples ref of optoelectronics include Optocoupler optical fiber Telecommunication communications See also AU Optronics Non radiative life time Ophir Optronics Photoemission Photoemission spectroscopy Photoemissivity Photovoltaic effect Optical fiber Preform Simrad Optronics Stimulated emission Thales Optronics Optical interconnect Light Peak Inter ... more details
Orphan date March 2009 Auto reignition is a process used in gas burner s to control ignition device s based on whether a burner flame is lit. This information can be used to stop an ignition device from sparking, which is no longer necessary after the flame is lit. It can also be used to start the sparking device again if the flame goes out while the burner is still supplying gas, for example, from a gust of wind or vibration. Kitchen appliances Most gas stove ranges and cooktops use sparking devices to ignite the burner flame. This eliminates the need for a pilot flame , which wastes energy. Most of these sparking device equipped ranges require the user to control the ignition sparking manually, resulting in a three step process required to operate the burner turn burner knob to a position that opens the gas valve and activates the sparking typically labeled Lite wait for ignition, typically 0.5 to 2 seconds turn burner knob past lite position, to stop the sparking noise and burning out the ignition electrode, to a desired flame intensity One implementation of a gas burner with auto reignition senses the electrical conductivity of the flame. This nonzero http www.durag.com html heg heglit.html flame conductivity is because combustion of natural gas releases enough free electrons to support a small current in air. An electronic circuit then starts or stops the igniter from sparking, based on whether the flame is lit. This reduces the number of steps to turn a burner on from three to one turn knob to a desired flame intensity while confirming flame ignites This is an elegant solution, compared to detecting flame via a thermocouple , a photoresistor or a mercury filled sensor. No extra components or electrical connections between the sparker electrode and the spark module electronics are required. This convenience and safety feature is found only as of June 2009 on higher priced gas ranges and cooktops. The case for requiring auto reignition as a safety feature Auto r ... more details
Image Scribbler robot.jpg thumb right The Scribbler robot used by IPRE in teaching introductory computer science courses The Scribbler is a small, low cost fully programmable intelligent robot with multiple sensor systems. It is capable of interacting with its environment. ref http parallax.com tabid 455 Default.aspx Parallax Inc. website, accessed 22 Sept. 2009 ref . It is capable of auto navigation. The Scribbler is a combined effort of three companies Parallax, Inc. company Parallax Inc. Element Products Inc. and Bueno Systems Inc. ref http robots.net article 1729.html Robots.net website, accessed 03 May 2010 ref As of May 2010, the Scribbler retails for around 100 USD. ref http www.google.com products?hl en&q scribbler robot&um 1&ie UTF 8&ei YY3fS nNY M8wSp3OiZBw&sa X&oi product result group&ct title&resnum 3&ved 0CCMQrQQwAg Google Shopping Search, accessed 03 May 2010 ref . A newer version of the Scribbler, Scribbler 2, will be coming out sometime in the fourth quarter Q4 2010. ref http www.parallax.com tabid 826 Default.aspx Parallax Site, accessed 03 May 2010 ref . The Scribbler has a built in BASIC Stamp 2 microcontroller brain. For inputting sensory information, the Scribbler has three photoresistor light sensors, infrared emitter, and infrared detector. Additional add ons can be bought to give the robot more capabilities through the serial port. For example, a bluetooth emitter receiver or a wireless card can be bought to interface with the robot. ref http robots.net article 1729.html Robots.net website, accessed 03 May 2010 ref . The Scribbler can be programmed through any BASIC Stamp Editor program, or through a GUI style interface, provided on Parallax s website. This uses different command tiles to control the motors and sensors. ref http www.parallax.com ProductInfo Robotics ScribblerRobotInformation ProgramtheScribblerRobot tabid 457 Default.aspx Parallax Product Page, accessed 03 May 2010 ref . Using a Myro library, you can also program the Scribble ... more details
The LA 2A Leveling Amplifier is an audio Dynamic range compression compressor originally produced by Universal Audio UREI and Teletronix Teletronix in 1965. Three versions of the LA 2A were made until 1969. ref http www.uaudio.com works pdf manuals LA 2A manual.pdf ref The LA 2A was inducted into the TEC Awards TECnology Hall of Fame TECnology Hall of Fame in 2004. ref http www.mixfoundation.org hof 04techof.html 13 ref The LA 2A is a hand wired, tube based, compressor. It uses a Electroluminescence electro luminescent panel together with a cadmium sulfide Photoresistor light dependent resistor to provide gain reduction, which, in the LA 2A, is called the T4 cell. The properties of the T4 give the LA 2A its unique character by making it an entirely program dependent design. The attack time is 10 milliseconds ref name JBL service manual and the release time is about 60 ms for 50 release and 0.5 to 5 seconds for full release, depending on the previous program material. ref name JBL service manual JBL vintage service manuals. http www.jblproservice.com pdf Vintage 20JBL UREI 20Electronics UREI LA 2A 20manual.pdf UREI LA 2A service manual. This Instruction Book was reprinted from text composed by the original manufacturer complete with errors and exaggerations . We feel the specification for attack time should have been in milliseconds, rather than microseconds. Retrieved on October 11, 2009. ref The LA 2A has simple controls a Peak Reduction knob controls the gain of the side chain circuit, and therefore, the gain reduction a Gain Control for make up gain and a Limit Compress switch which alter the compression ratio. The VU meter may also be switched to show gain reduction or output level. The LA 2A has a sonic character that make it sought after by many recording engineers. Quotation1 LA 2As warm things up. ...they EQ all the warmth and low mids and bass. When you put bass and drums in them they get fatter and bigger. And unless you hit them way hard and make the tube ... more details
Image PenguinRobot.jpg thumb right 300px Penguin Robot. The Penguin Robot is a bipedal robot with two directions of freedom, using two servos for walking. It is a precision machined 4 tall biped with an embedded BASIC Stamp 2px24 microcontroller. The Penguin walks forward with a tilt stride action and turns by sweeping both feet on the ground in opposite directions. Microprocessor The Penguin brain is based on a BS2PX24 module, which is the highest performing of all the BASIC Stamp microcontrollers, featuring the following technical specifications Processor Speed 32 MHz Turbo Program Execution Speed 19,000 instructions sec. RAM Size 38 Bytes 12 I O, 26 Variable Scratch Pad RAM 128 Bytes EEPROM Program Size 8 x 2K Bytes 4,000 Instructions Programming language PBASIC PBasic Input Output devices The Penguin includes the following I O devices 1 Hitachi HM55B Digital Compass sensor, which enables it to know its exact orientation 2 Photoresistor Photoresistors for light following avoidance 2 infrared Infrared emitters and an infrared infrared receiver for object detection 1 Blue seven segment LED for feedback 2 Micro servos for tilt and stride 1 Loudspeakers Piezoelectric speakers Piezospeaker in body underneath battery pack 1 Expansion port for connecting other input output components 1 Power switch located adjacent to battery pack 1 FTDI 232RL mini USB programming port used to download the software from the PC 1 Blue power indicator LED The robot is powered by 2 CR123 batteries. Assembling and programming The Penguin Robot is sold in kit, and requires a few hours to be assembled. It is not a pre programmed toy, but rather a hobbyist robot programming platform, since it operates according to the program that the user downloads in it. However, several ready to run programs are freely available, released by the supplier Parallax, Inc. company Parallax and by other users on the Web. Some of these programs allow it to sing, dance, move autonomously to North or toward the lig ... more details
Other uses Colourimeter disambiguation Colorimeter Not to be confused with a calorimeter . Unreferenced date May 2010 A colorimeter is a device used in Colorimetry chemical method colorimetry . In scientific fields the word generally refers to the device that measures the absorbance of particular wavelength s of light by a specific solution . This device is most commonly used to determine the concentration of a known solution solute in a given solution by the application of the Beer Lambert law , which states that the concentration of a solute is proportional to the absorbance. Construction Image Spectrophoto controls.svg thumb 300px 1 Wavelength selection, 2 Printer button, 3 Concentration factor adjustment, 4 UV mode selector Deuterium lamp , 5 Readout, 6 Sample compartment, 7 Zero control 100 T , 8 Sensitivity switch. The essential parts of a colorimeter are a light source often an ordinary low voltage filament lamp an adjustable aperture a set of colored Filter optics filters a cuvette to hold the working solution a detector usually a photoresistor to measure the transmitted light a meter to display the output from the detector In addition, there may be a voltage regulator , to protect the instrument from fluctuations in Mains power systems mains voltage . a second light path, cuvette and detector. This enables comparison between the working solution and a blank , consisting of pure solvent, to improve accuracy. Filters Changeable Filter optics optics filters are used in the colorimeter to select the wavelength of light which the solute absorbs the most, in order to maximize accuracy. The usual wavelength range is from 400 to 700 nanometre s nm . If it is necessary to operate in the ultraviolet range below 400 nm then some modifications to the colorimeter are needed. In modern colorimeters the filament lamp and filters may be replaced by several light emitting diode s of different colors. Cuvettes Main Cuvette In a manual colorimeter the cuvettes are insert ... more details
Photosensors or photodetectors are sensors of light or other Electromagnetic radiation electromagnetic energy. There are several varieties ref cite journal doi 10.1063 1.2884264 title Study of residual background carriers in midinfrared InAs GaSb superlattices for uncooled detector operation year 2008 last1 Haugan first1 H. J. first2 S. first3 F. first4 B. first5 G. J. first6 W. C. journal Applied Physics Letters volume 92 pages 071102 ref optics Optical detectors, which are mostly quantum devices in which an individual photon produces a discrete effect. Chemical detectors, such as photographic plate s, in which a silver halide molecule is split into an atom of metallic silver and a halogen atom. The photographic developer causes adjacent molecules to split similarly. Photoresistor s or Light Dependent Resistors LDR which change electrical resistance resistance according to light intensity Photovoltaic cells or solar cell s which produce a voltage and supply an electric current when illuminated Photodiode s which can operate in photovoltaic mode or photoconductive mode Photomultiplier tubes containing a photocathode which emits electron s when illuminated, the electrons are then amplified by a chain of dynode s. Phototube s containing a photocathode which emits electron s when illuminated, such that the tube conducts a current proportional to the light intensity. Phototransistor s, which act like amplifying photodiodes. Optical detectors that are effectively thermometers, responding purely to the heating effect of the incoming radiation, such as pyroelectric detector s, Golay cell s, thermocouple s and thermistor s, but the latter two are much less sensitive. Cryogenic detectors are sufficiently sensitive to measure the energy of single x ray, visible and near infra red photons. ref cite book author Enss, Christian Editor title Cryogenic Particle Detection publisher Springer, Topics in applied physics 99 year 2005 isbn 3 540 20113 0 ref Charge coupled device s CCD , ... more details
Refimprove date February 2009 An automatic headlight dimmer also called automatic beam control is a system to automatically switch between the low and high headlight beams on an automobile . Drivers could also use standard headlight dimmers such as foot operated devices to override the automatic headlight dimmer on cars so equipped. Early systems Unreferenced section date February 2009 General Motors Corporation General Motors introduced the first automatic headlight dimmer called the Autronic Eye in 1952, on their Cadillac and Oldsmobile models Buick , Pontiac and Chevrolet models began offering this feature in 1953. The system s photoresistor or phototube and associated circuitry were housed in a gunsight like tube on the dashboard. An amplifier module was located in the engine compartment that controlled the headlight relay using signals from the phototube unit. This early configuration went through two design iterations before being replaced after 1958 in favor of a system called GuideMatic in reference to GM s Guide lighting division. The GuideMatic had a more compact dashtop housing than the Autronic Eye, and a variable control knob that allowed drivers to adjust the system s sensitivity threshold to determine when the headlamps would be dipped from high to low beam in response to an oncoming vehicle. By the early 1970s, this option was withdrawn from all GM models except Cadillac , on which GuideMatic was available through 1988. Ford Motor Company Ford and Chrysler Corporation Chrysler built vehicles were also available with the GM made Autronic Eye and Guidematic dimmers from the 1950s through the 1980s. The automatic headlight dimmer called AutoDim was offered on several Lincoln automobile Lincoln models starting in the mid 1950s, and eventually the Ford Thunderbird and some Mercury automobile Mercury models had it available as well. Premium Chrysler Corporation Chrysler and Imperial automobile Imperial models offered a system called Automatic Beam Control ... more details
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