Chingrish LED Report (verbatim)
"I have connected with our engineers again and asked him to make some test reports to confirm our confusion about 190lm/w. The attachments are the test reports for 1W and 3W Bridgelux 17*34mil*9 for ...
Forum Discussion
"Illustrious Comrade Singing Butterfly LTD"?
And the following text is supposed to elucidate me as to the viability of lumen output per watt?
"Luminous intensity (Iv) does not represent the total light output from an LED. Both the luminous intensity and the spatial radiation pattern (viewing angle) must be taken into account. If two LEDs have the same luminous intensity value, the lamp with the larger viewing angle will have the higher total light output.
Theta one-half (q½) is the off-axis angle where the LED's luminous intensity is half the intensity at direct on-axis view. Two times q½ is the LEDs' full viewing angle; however, light emission is visible beyond the q½ point. Viewing angles listed in this catalog are identified by their full viewing angle (2q½ °).
LED viewing angle is a function of the LED chip type and the epoxy lens that distributes the light. The highest luminous intensity (mcd rating) does not equate to the highest visibility. The light output from an LED chip is very directional. A higher light output is achieved by concentrating the light in a tight beam. Generally, the higher the mcd rating, the narrower the viewing angle.
The shape of the encapsulation acts as a lens magnifying the light from the LED chip. Additionally, the tint of the encapsulation affects the LED's visibility. If the encapsulation is diffused, the light emitted by the chip is more dispersed throughout the encapsulation. If the encapsulation is non-diffused or water clear, the light is more intense, but has a narrower viewing angle. Non-diffused and water clear LEDs have identical viewing angles; the only difference is, water clear encapsulations do not have a tint to indicate color when the LED is not illuminated.
Overall visibility can be enhanced by increasing the number of LED chips in the encapsulation, increasing the number of individual LEDs, and utilizing secondary optics to distribute light. To illustrate, consider similar red GaAlAs LED chip technology in four different configurations: "
And the following text is supposed to elucidate me as to the viability of lumen output per watt?
"Luminous intensity (Iv) does not represent the total light output from an LED. Both the luminous intensity and the spatial radiation pattern (viewing angle) must be taken into account. If two LEDs have the same luminous intensity value, the lamp with the larger viewing angle will have the higher total light output.
Theta one-half (q½) is the off-axis angle where the LED's luminous intensity is half the intensity at direct on-axis view. Two times q½ is the LEDs' full viewing angle; however, light emission is visible beyond the q½ point. Viewing angles listed in this catalog are identified by their full viewing angle (2q½ °).
LED viewing angle is a function of the LED chip type and the epoxy lens that distributes the light. The highest luminous intensity (mcd rating) does not equate to the highest visibility. The light output from an LED chip is very directional. A higher light output is achieved by concentrating the light in a tight beam. Generally, the higher the mcd rating, the narrower the viewing angle.
The shape of the encapsulation acts as a lens magnifying the light from the LED chip. Additionally, the tint of the encapsulation affects the LED's visibility. If the encapsulation is diffused, the light emitted by the chip is more dispersed throughout the encapsulation. If the encapsulation is non-diffused or water clear, the light is more intense, but has a narrower viewing angle. Non-diffused and water clear LEDs have identical viewing angles; the only difference is, water clear encapsulations do not have a tint to indicate color when the LED is not illuminated.
Overall visibility can be enhanced by increasing the number of LED chips in the encapsulation, increasing the number of individual LEDs, and utilizing secondary optics to distribute light. To illustrate, consider similar red GaAlAs LED chip technology in four different configurations: "
