Note I asked about the resistor because connecting an LED without one is a sure way to destroy the LED. There are some very specific exceptions, but generally an LED requires a current limiting resistor.

Did you make your measurements at the points illustrated in the picture below?
View attachment 82044

Is this how you got your measurements of 3.7 VDC and 4.8 mA?
Ignore the two AA batteries... I just used them to represent your battery. (What are you using for a battery?)

@BobTPH, where are you getting on the order of 1 W? If we are to trust the OP figures (!), your original calculation seems right to me.

There is so much conflicting /extraneous information here and little hard facts. We need to know

• What is the LED
• What is its forward voltage
• What is its rated current
• What is the power source
• How are the measurements being taken.
• Forgot about the lumens

3.7 VDC and 4.8 mA are battry i used and put it with led work for ,3 hour
then lighiting drop dawen
so how waat led consum

 

The 1W comes from that fact the state of the lighting LEDs produce about 60 to 100 lm / watt. If the LED produces 70 lm, it is somewhere on the order of 1W.

Bob

if led 1w it was work for longer tim with battry

led is one of thes