Typical LED Characteristics

Transcription

1 Typical LED Characteristics Characteristic Unit Value Light output 1 mw > 1 2 Peak wavelength 3 nm 255 nm to 28 nm 4 Viewing angle Degrees 11 5 Full width at half maximum 3 (@1 ma) nm 16 Forward voltage (@ 1 ma) 6 V 9.8 FEATURES: Available in peak wavelengths from 255 nm to 28 nm Industry leading light output of 1 mw or higher Viewing angle of 11 Highest drive currents: up to 1 ma Industry best light output maintenance Hermetically sealed LEDs RoHS-compliant Forward voltage (@15 ma) 6 V 1.4 Thermal resistance, junction to case C/W 32 Notes: 1. LEDs are produced with semiconductor technology that is subject to process variation, yielding a range of flux performance that is approximately Gaussian in nature. To provide customers with fine granularity within the overall flux distribution, we separate LEDs into minimum optical power bins. 2. Optical power output measurement tolerance is ± 15%. Output power is measured using a 1 ma current pulse of < 1s duration at an ambient temperature of 25 C ± 5 C with the diode inserted into an integrating sphere. 3. Peak wavelength measurement tolerance is ± 2% 4. 5 nm bins 5. Viewing angle of 11 with a ball lens 6. Current tolerance is ± 5% Typical Radiation Pattern The LEDs are available with a nominal viewing angle of 11. The radiation pattern below shows the radiation pattern for a LED with a narrow viewing angle.

2 Spectral Power Distribution The plots below show the stability of the peak with various applied current and also shows that there is only one peak at the given wavelength. Note that the intensity of secondary peaks observed in the visible region is less than 1% of the maximum emission intensity in the UVC wavelength.

3 Relative Light Output vs. Junction Temperature The output power is very sensitive to junction temperature and care must be taken to keep the junction temperature as low as possible to get the best performance and lifetime. The plot below shows the change in optical power with the increase in junction temperature. Electrical Characteristics The typical forward voltage is less than 1 V at an operating current of 1 ma.

4 Mechanical Dimensions The LED is comprised of a steel header with a 2.5 mm copper slug, and a Kovar cap that is welded to the header to provide hermetic sealing. The cap contains a 7 mm ball fused silica window lens which provides the nominal viewing angle of 11. Header Dimensions Cap Dimensions

5 TYPICAL LED CHARACTERISTICS Characteristic Unit Value Light Output¹ mw 2² Peak wavelengths³ nm Viewing angle Degrees 12⁴ Full width at half maximum³ ma) nm <15 Forward voltage ma)⁵ V <1 Forward voltage (@15 ma)⁵ V <12 Notes: 1. LEDs are produced with semiconductor technology that is subject to process variation, yielding a range of flux performance that is approximately Gaussian in nature. To provide customers with fine granularity within the overall flux distribution, Crystal IS separates LEDs into minimum optical power bins. 2. Optical power output is measured at 25 C ± 5 C with the diode inserted into an integrating sphere. The measurement tolerance is ± 15%. 3. Peak wavelength measurement tolerance is ± 2%. 4. Viewing angle is the off axis angle from the lamp centerline where the optical power is 1/2 of the peak value. 5. Current tolerance is ± 5%. Thermal resistance, junction⁶ to case C/W 1 6. Junction refers to the area of the LED where heat (and light) is generated. FEATURES Available in peak wavelengths from 25 nm to 28 nm Industry leading light output. Diode samples available in bins of 5 mw, 1 mw, 2 mw and higher. Viewing angle of 12 Drive currents of 15 ma and higher Industry best light output maintenance RoHS-compliant

6 TYPICAL RADIATION PATTERN The SMD LEDs have nominal viewing angles of 12. The Lambertian radiation pattern is shown below. LAMBERTERIAN RADIATION PATTERN Normalized Intensity, a.u Spectral Power Distribution The plots below show the stability of the peak with various applied current and also shows that there is only one peak at the given wavelength. Note that the intensity of secondary peaks observed in the visible region is less than 1% of the maximum emission intensity in the UVC wavelength. INTENSITY VS. WAVELEGTH FOR VARYING CURRENTS PEAK λ = 264 nm 5 4 Intensity ma 1 ma 15 ma Wavelength, nm

7 Relative Light Output vs. Junction Temperature The output power is very sensitive to junction temperature and care must be taken to keep the junction temperature as low as possible to get the best performance and lifetime. The plot below shows the change in optical power with the increase in junction temperature. TYPICAL LIGHT OUTPUT CHARACTERISTICS OVER TEMPERATURE Relative Light Output (%) Junction Temperature (T J ), C Electrical Characteristics The typical forward voltage is less than 12 V at an operating current of 15 ma. TYPICAL I-V CHARACTERISTIC.15 Current, A Voltage, V