The Development of a Robust Accelerometer-Based Start of Combustion Sensing System

Polymer nanofibers are nanoscale materials whose properties can be adjusted to provide desirable light management performance for high efficiency solid-state lighting luminaires. The polymeric nanofibers at the core of this project have diameters on the order of 100 to 1000 nm and a length of more than 1 cm. By controlling fiber diameter, fiber packing, and fiber morphology, a low cost, high performance optical material can be fabricated. This report describes the fabrication of these nanofiber structures and their uses and benefits in solid-state lighting application. When used in solid state lighting devices, nanofibers can take the form of either diffuse reflectors or photoluminescent materials. Nanofiber reflectors (NFR) were developed which displayed high diffuse reflectance with reflectance values in excess of 0.90. In contrast, traditional reflector materials such as aluminum and paint typically possess reflectance values below 0.80 and absorb a larger fraction of light, reducing luminaire output efficiency. The incorporation of the NFR technology into reflectors, troffers, and beam formers present in SSL luminaires provides better reflectance and lower light loss than is possible with conventional materials. Photoluminescent nanofibers (PLN) can be formed by combining nanofibers with photoluminescent materials such as phosphors and quantum dots (QD). Forming the PLN with the proper combination of green and red luminescent materials and exciting the nanocomposite with a blue light emitting diode (LED) has been demonstrated to produce high efficiency (> 55 lumens per watt) white light with excellent color rendering properties. The incorporation of QDs in the PLN is particularly advantageous in that this approach enables the correction of any color deficiencies in the light source without creating unnecessary radiation in the near infrared. Cost models developed during this project have demonstrated that both the NFR and PLN materials can be mass produced at a manufacturing cost of less than $5 per square foot, making it commercially attractive. To capitalize on the benefits of nanofiber technologies in solid-state lighting, several new remote phosphor reflector configurations were developed in the project. When combined with these unique lighting designs, nanofibers have a number of demonstrated benefits in lighting devices including: (1) Providing high quantum efficiency down-conversion of LED wavelengths to produce full spectrum white light; (2) Enabling tunable device structures that achieve colors ranging from warm white to cool white with high CRIs; (3) Supplying mass producible, cost-effective solutions for diffuse, high reflectance light management across the visible spectrum; (4) Facilitating remote phosphor luminaire designs that increase the lifetime and performance of luminescent materials; and (5) Providing conformability to geometries imposed by the light fixture enabling new lighting designs. This report provides a review of the activities conducted during this project and the major advances that have been made during this work in the field of nanoscale materials for solid-state lighting. Section 1 provides background on the nanofiber technologies and patent-pending luminaire structures developed during this project. Section 2 provides a detailed discussion of the benefits of the technologies developed during this work. Section 3 compares the execution of this project with the original proposal. A high level summary of the findings from each Task is also provided in the section. Section 4 lists the products (i.e., patent applications, presentations, publications, collaborations) that have been developed during this project. More details on work conducted during Budget Periods 1-3 can be found in Appendices A-C. The technologies developed during this program have significant commercial potential, and there has already been strong interest in these breakthroughs from the lighting community. It is anticipated that these technologies will begin appearing in commercial products in roughly 5 years to provide significant energy savings for the United States