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Google should have the answer, but first you need to decide what is a 'standard' red LED. Different manufacturers have different ideas! LEDs even from the same batch will have different, current-dependent luminosities.
Hi Alex, I just bought an LED from an electronic shop so I have no idea about manufacturer and they told me this is the standard red led. The glass is in red colour.
Do you even know what the definition of luminosity is? Or how to measure it? Usually we talk about LED brightness instead of luminosity. There is no such thing as a "standard" LED. What you have could be a considered a "typical" LED though. You can power that puppy up with a five or six or even nine volts DC from either a battery of a "wall wart" supply, and probably with a 1.2 to 1.5 V dry cell as well, if you place an appropriate resistor in series with it to limit the LED current to a "safe" level that won't destroy the LED. Try starting out with a 1000 ohm, 1/2 watt, resistor and working your way downward in resistance from there. Stop when you reach the desired "luiminosiity" or until the LED burns out.