The Kynix Blog - LED

A few months ago,I have see an article about desinging a nixie tube clock with an ATmega328 and ESP8266,and I had a big interest in it and I made one immediately according to the article's step.The ESP8266 connected to a Network Time Protocol (NTP) server was cheaper to implement than using an RTC due to the discrepancies between the defined clock speed and actual clock speed.  You can see the picture,nixie tubes came into existence during the time of vacuum tubes and before LEDs (at least in the context of the Soviet Union). Once LED technology made its way into the USSR, nixie tubes began to fade out. Even today when shopping for nixie tubes online, all of the tubes I’ve purchased have been sent from either Russia or Ukraine. It seemed fitting that I would follow in history’s footsteps and switch over to the cheaper, easier and safer LED technology (I may or may not have shocked myself a few times on the 170VDC supply when testing).  I would like to use seven-segment displays to solve this problem. However,I think it's a little expensive even today. I would like to try something different, something that you don't really see sommercially. Suddently,binary clocks come to my mind,it's interested programmer like me. After a time of consideration, I sticked with a digital display and kept going back to the seven-segment variety. Using our OLED breakout allowed me to recreate the look of a 7-segment display, but I can add animations when the digits change. I added animations that make the individual segments drop in and fall off of the display when the time changes.In my nixie tube clock,I first tried using ESP8266 control both WIFI and the nixie tubes,but the WiFi stack was just too large to avoid seeing the multiplexed nixie tubes flicker any time the 8266 needed to do something WiFi-related. This meant that I had to have two controllers on the board; an ATmega328 would handle the nixies, and the ESP8266 would be responsible for the time and web GUI for settings. After that, I found ESP32 Thing from Sparkfun when I browse google, The ESP32 have two cores, one is to hanle the wifi stack and the other for programming. and I thought of my clock immediately and  how much easier it would be to just have one device to program and not worry about how I would transfer information between the two. About the Clock Stands  See the above picture,my clock is still work in progress currently,the code requires hard coding the SSID and password for the wireless access point. I really liked the web GUI I made, which I can access from the ESP8266 to change settings for the access point’s SSID and password or to select the NTP server location, time zone and whether or not to adjust for daylight saving time. I have two problems now. The one is that I haven’t been able to implement the GUI quite yet due to library changes in WiFi.h to serve web pages, and this is where I could use some help. If you’ve made a web server for your ESP32, please let me know how you handled multiple pages. I’ve been scratching my head throughout the build on how to get this done. With the ESP8266, there’s on(const String &uri, handler function), but that seems to have been removed on the ESP32. And the another problem with both clocks is how I handle daylight saving. Currently with the nixie clock, I have a selection box that removes an hour, but I would like to have that happen automatically. The NTP time returned will allow me to figure out the date, but given that daylight saving time begins on the second Sunday of March and ends on the first Sunday of November, how would you efficiently program in that functionality? The clock is far from finished, and aside from the problems I’ve mentioned above, there are some minor things I would like to touch up and a couple of extra features I’d like to add. And a part of my code is as following:#include <SPI.h>  // Include SPI if you're using SPI#include <TimeLib.h>#include <WiFi.h>#include <WiFiUdp.h>#include <SFE_MicroOLED.h>  // Include the SFE_MicroOLED library const char ssid[] = "************";  // your network SSID (name)const char pass[] = "************";  // your network password static const char ntpServerName[] = "time.nist.gov";const int timeZone = -6;  // Mountain Daylight Time WiFiUDP Udp;unsigned int localPort = 8888;  // local port to listen for UDP packets time_t getNtpTime();void sendNTPpacket(IPAddress &address); //IO Pin Constants//Digit 0#define PIN_RESET_0 12#define PIN_DC_0    22#define PIN_CS_0    13 //Digit 1#define PIN_RESET_1 17#define PIN_DC_1    22#define PIN_CS_1    16 //Digit 2#define PIN_RESET_2 4#define PIN_DC_2    22#define PIN_CS_2    0 //Digit 3#define PIN_RESET_3 2#define PIN_DC_3    22#define PIN_CS_3    15  //7-Seg Pixel Constants for OLED#define A_X 59#define A_Y 14 #define B_X 35#define B_Y 38 #define C_X 6#define C_Y 38 #define D_X 0#define D_Y 14 #define E_X 6#define E_Y 7 #define F_X 35#define F_Y 7 #define G_X 29 #define G_Y 14 //Initialize DisplaysMicroOLED oled0(PIN_RESET_0, PIN_DC_0, PIN_CS_0);MicroOLED oled1(PIN_RESET_1, PIN_DC_1, PIN_CS_1);MicroOLED oled2(PIN_RESET_2, PIN_DC_2, PIN_CS_2);MicroOLED oled3(PIN_RESET_3, PIN_DC_3, PIN_CS_3); bool updateTime=1;byte old_minute=0,old_hour=0; time_t prev = 0, prevNow=0; void setup() {  Serial.begin(115200);   //Setup Displays  oled0.begin();  oled0.clear(PAGE);  oled1.begin();  oled1.clear(PAGE);  oled2.begin();  oled2.clear(PAGE);  oled3.begin();  oled3.clear(PAGE);    // Connect to WiFi  WiFi.begin(ssid, pass);   pinMode(5,OUTPUT);  //Use the built in LED for WiFi Connection Status  bool state = 0;  while (WiFi.status() != WL_CONNECTED) {    delay(500);    Serial.print(".");    state = !state;    digitalWrite(5,state);  }  digitalWrite(5,HIGH);   Serial.print("IP number assigned by DHCP is ");  Serial.println(WiFi.localIP());  Serial.println("Starting UDP");  Udp.begin(localPort);  Serial.println("waiting for sync");  setSyncProvider(getNtpTime);  setSyncInterval(300);   //Display Current Time  Update_Digit(oled0,hourFormat12()/10,32);  Update_Digit(oled1,hourFormat12()%10,32);  Update_Digit(oled2,minute()/10,32);  Update_Digit(oled3,minute()%10,32);  prev = now();  prevNow = now()/60;} void loop() {  yield();  //Let the ESP32 handle the wifi stack   //Print the current time to Serial (debugging)  if(now() != prevNow)  {    prevNow = now();    Serial.print(hour());    Serial.print(' ');    Serial.print(minute());    Serial.print(' ');    Serial.print(second());    Serial.println();  }   //Only update when the minutes change  if(now()/60 != prev)  {    prev = now()/60;     //Update Display    for(byte i=0;i<33;i++)    {      if(hour() != old_hour)  //Does hour need to be updated?      {        if((hour()/10)!= old_hour/10) //Which hour digit needs to update? Both?        {          Update_Digit(oled0,hourFormat12()/10,i);          Update_Digit(oled1,hourFormat12()%10,i);        }        else  //Just update the first hour digit        {          Update_Digit(oled1,hourFormat12()%10,i);        }              }       if(minute() != old_minute)  //Does the minutes need to updated?      {        if((minute()/10)!= old_minute/10) //Which digit needs to be updated? Both?        {          Update_Digit(oled2,minute()/10,i);          Update_Digit(oled3,minute()%10,i);        }        else  //Just update the first minute digit        {          Update_Digit(oled3,minute()%10,i);        }              }      delay(5); //Wait 5ms to slow down the animations    }    old_hour = hour();    old_minute = minute();  }} //Animations for changing numbersvoid Update_Digit(MicroOLED &oled,byte number, byte i){  oled.clear(PAGE);  switch(number)  {    case 0:      if(i<17)      {        oled.rectFill(A_X+(64-i*4),A_Y,4,22); //A        oled.rectFill(A_X-(i*3.6),A_Y,4,22); //A        oled.rectFill(B_X,B_Y,22,4); //B        oled.rectFill(C_X,C_Y,22,4); //C        oled.rectFill(E_X+(32-i*2),E_Y,22,4); //E        oled.rectFill(F_X+(32-i*2),F_Y,22,4); //F        oled.rectFill(G_X-(i*4),G_Y,4,22); //G      }      else          break;     case 1:      oled.rectFill(A_X-(i*2),A_Y,4,22); //A      oled.rectFill(B_X,B_Y,22,4); //B      oled.rectFill(C_X,C_Y,22,4); //C      oled.rectFill(D_X-(i*2),D_Y,4,22); //D      oled.rectFill(E_X-(i*2),E_Y,22,4); //E      oled.rectFill(F_X-(i*2),F_Y,22,4); //F    break;    default:    break;  }  oled.display();}

There is no doubt that the use of LCD headlamp is a succcessful further step towards digitalizing lighting. LCD headlamp which enables complex functions will also be relevant to autonomous driving. Let's talk something about the following research project about developing a headlamp basics on a LCD (  Full name is Liquid Crystal Display )which made by HELLA and seceral partners.This technology is an good example already known in the home entertainment field.  About The ProjectIn the context of the research project funded by the Federal Ministry of Education and Research (BMBF) regarding the fully adaptive light distribution for intelligent, efficient and safe vehicle lighting (VoLiFa2020), HELLA has developed a headlamp on the basis of a Liquid Crystal Display (LCD) in collaboration with project partners Merck, Institut für Großflächige Mikroelektronik IGM, Stuttgart University, Porsche, Elmos Semiconductor, Schweizer Electronic, and the University of Paderborn. Complex FunctionsIn general,the new LCD headlamp projects 30.000 pixels onto the road. This allows adjusting the light pattern in an intelligent and continuous manner to various driving situations in real time. The use of an LC display is a further step towards digitalizing lighting. This means: the adaptation of the light pattern will increasingly be determined by software. The driver will obtain the best possible view of the road. Individual segments with e.g. other traffic participants or strongly reflecting street signs can be omitted or dimmed in a targeted manner. Highly complex functions are also conceivable: navigation arrows or lines showing the ideal lane can be projected onto the road. LCD technology enables functions that will also be relevant to autonomous driving.  The LC display is the headlamp’s key component. It is situated between the LED light source and the projection lens. The display generates a matrix with 100 x 300 pixels that can be individually controlled and dimmed. A camera installed in the vehicle as well as a sensor optically reading distances and speeds (light detection and ranging sensor, LiDAR), will forward the ambient information to the headlamp control unit via a processor. This will then direct the individual display pixels up to 60 times per second. 25 high-power LED’s arranged in three rows will serve as light source. Each LED’s light intensity will be adjusted to the respective lighting situation. Due to increasing traffic volumes and safety requirements, intelligent lighting systems are of increasing importance. LCD technology enables completely new functionalities and opportunities here. And the use is not limited to passenger cars. Other vehicle categories, such as commercial vehicles or buses also provide meaningful application areas. ThanksgivingThanks to this project's great resolution and sharpness of detail, it opens up a diffirent new paths in automotive lighting technology. 

Today I want to share an LED strobe design project I found in electronic-lab, which you can do it by yourself. Strobe provides regular flashes of light. Usually Strobes are designed using Xenon Tubes. Here is LED based simple solution that can be used as strobe for entertainment and events and also as warning signals. Project is based on PIC16F1825 micro-controller with two digit frequency display. Project provides TTL output signal, frequency 1Hz-25Hz, Tact switches provided to set the frequency. This project works along with DC Output Solid State Relay Features 1.Supply 4.5 to 5V DC2.Frequency 1Hz To 25Hz3.Easy Interface with Relay Board4.Easy Interface with Solid State Relay5.On Board Power LEDOn Board Output LED6.Onboard Switch to set the frequency7.2X7 Segment 0.5 Inch Display Applications 1.Strobe for Entertainment2.Traffic Signal3.Warning Signal4.Ambulance Warning Signals Schematic   Parts List Connections Photos Working Diagram Ref.PIC16F1825 

Today I want to share a project of making a simple automatic street light controller using relay and LDR I found in circuitdigest with you.   You have seen street light which automatically gets turned on in the night and gets turned off in the morning or day time, there are sensors who senses the light and control the light accordingly. These Street lights are an important project in smart cities.   So here in this project, we are going to make a Simple Automatic Street Light Controller Using Relay and LDR. This circuit is very simple circuit and can be built with Transistors and LDR, you don’t need any op-amp or 555 IC to trigger the AC load. Here we have used an AC bulb as street light. Some applications of this circuit are street light controlling, home/office light controlling, day and night indicators, etc.   Components Required:   Transistor BC547 -2 LDR (Light Dependent Resistor) Relay Resistor 1k 100k Potentiometer Power Supply 12v -1 Connecting wires Jumper wires Screw terminal Block 2 pin or 3 pin Bread Board or Perf Board 1n4007 Diode AC supply AC Load or Bulb   Here you may want to know: what is LDR? LDRs are made from semiconductor materials to enable them to have their light sensitive properties. There are many types but one material is popular and it is cadmium sulphide (CdS). These LDRs or PHOTO REISTORS works on the principle of “Photo Conductivity”. Now what this principle says is, whenever light falls on the surface of the LDR (in this case) the conductance of the element increases or in other words the resistance of the LDR falls when the light falls on the surface of the LDR. This property of the decrease in resistance for the LDR is achieved because it is a property of semiconductor material used on the surface. LDR (Light Dependent Resistor)   Circuit Diagram and Explanation:   Below is the circuit diagram of this Light sensing Street Light:       In this project, we have used an LDR (Light Dependent Resistor) which is responsible for detecting light and darkness. The resistance of LDR increases in darkness and reduces in presence of light. This circuit is same as a Dark Detector or Light Detector Circuit, only here we have replaced simple LED with a AC load, using a Relay. Two BC547 NPN transistors are used to drive the relay. Automatic Street Light circuit using LDR and relay   Whenever light falls over LDR its resistance get decreased and transistor Q1 turns ON and collector of this transistor goes LOW, and this makes the second transistor turns OFF due to getting a LOW signal at its base, so relay also remain turned OFF due to second transistor.   Now whenever LDR senses Darkness, mean no light, then transistor Q1 turned ON due to increase in the resistance of LDR which is responsible for voltage drop at the base of Q1. Due to a LOW signal at the Q1 base, Q2 transistor gets a HIGH signal from the collector of Q1 and turns ON the relay. Relay turned ON the AC load that is connected to relay. A 10K pot is also used for setting up the sensitivity of the circuit.   So this is how automatic Street Lights turns on in the night and turn off in the day, and below is the effect pictures. >>>>>                                                       > >>>>   Ref. KY56-BC547A KY32-1N4007  

When designing a custom lighting solution, there are many different goals to take into consideration. One of the most essential may be reducing the power supply needs of the system. Doing so can provide further benefits, such as improving reliability and expected shelf life, and reducing space and size constraints. Benefits often come with tradeoffs; traditionally, when you reduce power you may need to reduce brightness at the same time. The good news is that this doesn’t always have to be the case. GLOBAL LIGHTING TECHNOLOGIES have compiled a list of five smart ways that you can reduce power without sacrificing LED brightness. 1. LED efficiencyHow do you do more with less? It's all about efficiency, and choosing more efficient LEDs can make a world of difference. Choosing a more efficient LED may seem like a more expensive option, but keep in mind that it’s not just about the cost of the LED - what you should really be considering is the cost per Lumen of output. A more efficient LED is actually more cost-effective, while simultaneously helping reduce power needs. 2. Lightguide material efficiencyAny light which is absorbed by the lightguide material is light that the actual display is losing. Therefore, switching to a material with a higher transmissivity to improve efficiency and it will aid in the retention of more light. 3. LED driver circuitBy utilising a highly efficient LED driver circuit, you can prevent power loss and improve the end result. This is often overlooked, as many engineers design circuits which use resistors to reduce voltage and match current to the LEDs. You can prevent those power losses from occurring by using custom designed LED driver chips and circuits with improved efficiency. 4. Lightguide extraction efficiencyAnother area where efficiency can be improved is with extraction, and by doing so more light is able to reach the user’s target area. In turn, power can also be reduced. Our innovative extraction technology offers higher efficiency and overall improved extraction, helping to achieve this goal. 5. LightguidesThe job of a lightguide is to take the light from the LED and spread it out uniformly over the surface being illuminated. With the right design and technology, a custom lightguide can actually conserve most of the initial LED efficiency while greatly increasing uniformity of the display, offering the best of both worlds. Ref.KY32-HV9921N3KY32-MIC2287CBD5KY32-LNK456DG

The US Department of Energy (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) has detailed a living laboratory test of solid-state lighting (SSL) and controls on a 40,000-ft2 floor in a New York commercial office building. Berkeley Lab worked with the Building Energy Exchange (BEEx) on the LED lighting project that also included comprehensive light and occupancy sensors along with connected window shade controls. Berkeley Lab believes the work will speed market adoption of smart lighting and the BEEx will use the work to further its educational mission, serving lighting designers and specifiers that are working on commercial spaces.Lately, much of our coverage about smart lighting and the Internet of Things (IoT) has been focused on what lighting-based connectivity can offer in supporting new applications and services such as indoor positioning, security, asset tracking, and more. For example, Acuity Brands said earlier this year that it has deployed indoor positioning technology in 20 million ft2 of retail space. The IoT hype can make it easy to forget that networked control of lighting and shades confined to a space such as an office floor can deliver tremendous benefits in energy used.Still, roadblocks to more smart lighting installations remain. “Context matters when it comes to figuring out where the market barriers are with respect to contractors, facility managers, and office workers — isolated tests in a laboratory environment are often not enough,” said Eleanor Lee. “Reducing stakeholders’ uncertainty about performance and occupant response in a real-world setting can be critical to accelerating market adoption.” Lee is the Berkeley Lab scientist that led the New York project intended to document the benefits of smart lighting in a working office space — thus the characterization as a living lab. Berkeley Lab and BEEx collaborated on an office smart lighting trial in New York City that combined SSL with sensors and window shade controls. Indeed, the project team monitored energy usage and other characteristics of the office space for a full year before the retrofit to SSL and controls took place. BEEx acted as the local manager of the project.As the nearby photo illustrates, the retrofit replaced fluorescent T5 lighting with dimmable LED fixtures delivering direct and indirect lighting. The floor-to-ceiling windows received automated shades. And connected sensors spread throughout the mostly-open space can detect localized light levels and occupancy.The test further considered thermal elements of the space given that the ubiquitous windows and daylight can heat a space. The test included the use of linear slot diffusers along the top of the windows that can mitigate rising temperatures. And underfloor air distribution (UFAD) diffusers were used to improve airflow and allow for localized control. Thermal imaging was used to document acceptable temperatures throughout the retrofitted space.The smart lighting project sought to balance the benefits of natural light with visual and thermal comfort and provide workers with enjoyable views when possible. Shades had to be lowered at times to mitigate glare but could be opened at other times, both reducing the need for artificial lighting and fully revealing views for the office.The study focused on the 40-ft perimeter zone of the office floor. Compared to the measured baseline, the electricity required for lighting dropped 79% over the course of six months in which BEEx has monitored the installation. Peak electrical demand dropped 74%.The study did not measure energy dedicated to powering the HVAC (heating, ventilation, and air conditioning) system in the space. But the researchers did estimate the impact on HVAC energy and also projected the measured data to suggest an entire building retrofit would have delivered savings of $730,000 per year. Based on installation cost of $3–$10 per square foot, an entire building project would pay back in 3–12 years.BEEx will take the results of the project to help the lighting community with tools and other resources. “Using everything we learned on this project,  we've developed a series of tools that will really help the engaged design professional or building owner make better decisions about lighting system upgrades, and avoid the common pitfalls on the road to a high-performance office space,” said Yetsuh Frank, BEEx managing director of strategy and programs.The Berkeley Lab has not been as involved in the SSL sector as has the DOE Pacific Northwest National Laboratory (PNNL). PNNL has been behind many of the DOE Caliper and Gateway projects. We have covered many of those reports such as a recent Gateway report on four common indoor lighting applications.Still, the Berkeley Lab is adding to the DOE’s SSL initiative. About a year back we reported on a Berkeley project involving solar-powered LED lighting outdoors where the researchers said such lighting could create 2 million jobs in developing regions. Ref.591-2201-013F591-2001-013F