Brückner, Stefan ; Vinh, Trinh Quang ; Khanh, Tran Quoc
:
Double-binned LEDs reduce inhomogeneity in rearlamps?
[Online-Edition: http://www.emk.tu-darmstadt.de/lt/forschung/publikationen/20...]
In: International Symposium on Automotive Lighting, September 2011, Darmstadt.
In: International Symposium on Automotive Lighting
, 9
.
Darmstadt
[Konferenz- oder Workshop-Beitrag], (2011)
Kurzbeschreibung (Abstract)
When developing automotive rearlamps employing multiple LEDs manufacturers face inhomogeneity problems. Realizing brake and taillight with the same LEDs introduces the need of dimming these LEDs. Widely used dimming methods are Pulse Width Modulation (PWM) and Constant Current Reduction (CCR). CCR has several advantages over PWM, including flicker-free operation and energy efficiency. On the downside, CCR can cause inhomogeneity in rearlamps, at least in combination with traditional single binned LEDs. Recently introduced double-binned LEDs are selected (binned) at two different forward currents, according to brake and taillight level. Thus, the perceived inhomogeneity could be reduced.
In our Lab we measured a number of double binned red rearlamp LEDs. For comparison reasons, we also measured single binned LEDs of the same type. We present an analysis of the results, giving answers if the spread in luminous flux or dominant wavelength changes with forward current or temperature, and if these changes lead to drop out of the ECE color range or if they are noticeable by the human eye.
| Typ des Eintrags: | Konferenz- oder Workshop-Beitrag (Keine Angabe) |
|---|---|
| Erschienen: | 2011 |
| Autor(en): | Brückner, Stefan ; Vinh, Trinh Quang ; Khanh, Tran Quoc |
| Titel: | Double-binned LEDs reduce inhomogeneity in rearlamps? |
| Sprache: | Englisch |
| Kurzbeschreibung (Abstract): | When developing automotive rearlamps employing multiple LEDs manufacturers face inhomogeneity problems. Realizing brake and taillight with the same LEDs introduces the need of dimming these LEDs. Widely used dimming methods are Pulse Width Modulation (PWM) and Constant Current Reduction (CCR). CCR has several advantages over PWM, including flicker-free operation and energy efficiency. On the downside, CCR can cause inhomogeneity in rearlamps, at least in combination with traditional single binned LEDs. Recently introduced double-binned LEDs are selected (binned) at two different forward currents, according to brake and taillight level. Thus, the perceived inhomogeneity could be reduced. In our Lab we measured a number of double binned red rearlamp LEDs. For comparison reasons, we also measured single binned LEDs of the same type. We present an analysis of the results, giving answers if the spread in luminous flux or dominant wavelength changes with forward current or temperature, and if these changes lead to drop out of the ECE color range or if they are noticeable by the human eye. |
| Buchtitel: | 9th International Symposium on Automotive Lighting |
| Reihe: | International Symposium on Automotive Lighting |
| Band: | 9 |
| Ort: | Darmstadt |
| Freie Schlagworte: | LED, rearlamps |
| Fachbereich(e)/-gebiet(e): | Fachbereich Elektrotechnik und Informationstechnik > Institut für Elektromechanische Konstruktionen > Lichttechnik Fachbereich Elektrotechnik und Informationstechnik > Institut für Elektromechanische Konstruktionen Fachbereich Elektrotechnik und Informationstechnik |
| Veranstaltungstitel: | International Symposium on Automotive Lighting |
| Veranstaltungsort: | Darmstadt |
| Veranstaltungsdatum: | September 2011 |
| Hinterlegungsdatum: | 19 Jan 2012 13:05 |
| Offizielle URL: | http://www.emk.tu-darmstadt.de/lt/forschung/publikationen/20... |
| Export: |
Optionen (nur für Redakteure)
 |
Eintrag anzeigen |
Drucken
Impressum