In this study, we propose an indoor navigation system that utilizes visible light communication technology, which employs LED lights and a geomagnetic correction method, aimed at supporting visually impaired people who travel indoors. To verify the effectiveness of this system, we conducted an experiment targeting visually impaired people. Although acquiring accurate positional information and ...

Red (SrCa)AlSiN3: Eu nitride phosphor with different particle sizes were characterized based on physical and luminescent properties, then packaged into Chip-On-Board (COB) Warm White Light Emitting Diode (LED) modules to investigate the influence of particle size on packaging parameters and optical output of the COB LED devices. The phosphor particle sizes investigated were 10μm, 12μm and 14μm,...

While LEDs themselves are extremely reliable and have a long lifetime, are electronic LED drivers capable of providing the required current/voltage input to the LEDs over their whole lifetime? This paper aims to address the above question in general and for the Xitanium family of LED drivers developed by Philips Lighting specifically. It will describe some of the strategies which Philips applie...

The experiments were carried out in 2009 in phytotron chambers and commercial greenhouses of the Lithuanian Institute of Horticulture. The frigo plants of ‘Elkat’ strawberries (Fragaria x ananassa Duch.) were investigated. The frigo sprouts were grown in a phytotron chamber for a month under different light-emitting diode (LED) treatment: sole red (640 nm) light, photosynthetic photon flux dens...

We examined the effects of light quality on growth characteristics and porphyrin biosynthesis of rice seedlings grown under different wavelengths from light emitting diodes (LEDs). After 10 days of exposure to various wavelengths of LEDs, leaf area and shoot biomass were greater in seedlings grown under white and blue LEDs than those of green and red LEDs. Both green and red LED treatments dras...

BACKGROUND We observed that a dim, red light-emitting diode (LED) triggered by activity increased the circadian periods of lab mice compared to constant darkness. It is known that the circadian period of rats increases when vigorous wheel-running triggers full-spectrum lighting; however, spectral sensitivity of photoreceptors in mice suggests little or no response to red light. Thus, we decided...

The aim of this study was to investigate the effect of industrially designed light-emitting diode (LED) lamp lighting on the nutritional quality of Brassicaceae microgreens. Red pak choi (Brassica rapa var. chinensis ‘Rubi F1’), tatsoi (Brassica rapa var. rosularis) and mustard (Brassica juncea L. ‘Red Lion’) were grown in a greenhouse (20±2/18±2 °C) during winter season, and the solar daily in...