WHAT IS LDR ? اهو وري ايل ڊي آر ڇا آهي؟ پريشان ڇو پيا ٿيو ! آئون آهيان نه سولي سڌيءَ ۾ سمجهائڻ وارو. هي هڪ اهڙي قسم جو ريزسٽر ۽ ايجاد آهي جنهن جو دارومدار روشنيءَ تي ٿئي ٿو معنيٰ روشنيءَ سان ايڪٽيويٽ ٿئي ٿو تنهنڪري هن کي (لائيٽ ڊپينڊنٽ ريزسٽر) يا فوٽو ريزسٽر به چئبو آهي. You’re asking what is LDR? It stands for (Light Dependent Resistor) or (Photoresistor), which is a passive electronic component, basically a resistor which has a resistance that varies depending of the light intensity. A photoresistor is made of a high resistance semiconductor that absorbs photons and based on the quantity and frequency of the absorbed photons the semiconductor material give bound electrons enough energy to jump into the conduction band. The resulting free electrons conduct electricity resulting in lowering resistance of the photoresistor. The number of electrons is dependent of the photons frequency. سوال اُڀي ٿو ته اهو ڪم ڪيئن ٿو ڪري : How does the LDR (photoresistor) works The resistance is very high in darkness, almost high as 1MΩ but when there is light that falls on the LDR, the resistance is falling down to a few KΩ (10-20kΩ @ 10 lux, 2-4kOmega; @ 100 lux) depending on the model. اونده ۾ هن جي ريزسٽنس هاءِ رکبي آهي يعني تقريبن هڪ ميگا اوهم ۽ جڏنهن ان تي لائيٽ وجهبي ته ته اها ريزسٽنس ڪري (ڊراپ ٿي) ڪي اوهم وڃي بچندي. Light dependent resistors come in different shapes and colors. LDRs are very useful in many electronic circuits, especially in alarms, switching devices, clocks, street lights and more. There are some audio application uses such as audio limiters or compressors. It is used to turn ON or OFF a device according to the ambient light. هي مختلف شڪلن ۽ رنگن۾ بازار ۾ ملن ٿا انهن کي مطتف اليڪٽرانڪي نظام ۾ ڪم آڻبو آهي، جهڙوڪ الارمس ۾، سئچنگ ڊواسز ۾، واچن ۾، اسٽريٽ لائيٽس ۾، ۽ ٻين گهڻن ئي ڪمن ۾.
