Optical Engineer for Non-Combustible Sparkler Illusion Feasibility Study

I am seeking an experienced optical/illumination engineer to perform a paid, fixed-price feasibility study for a wearable, battery-powered, non-combustible lighting product. A working addressable-LED prototype already exists. However, firmware and animation improvements alone have not produced the required visual effect. The current system still appears too much like illuminated LEDs rather than an irregular, spatially dynamic spark-like optical phenomenon. The purpose of this project is NOT to develop the complete product, redesign the mechanical enclosure, write firmware, or perform open-ended experimentation. I need an expert to determine whether a materially better visual effect is technically achievable through a different optical or illumination architecture while maintaining the following constraints: Wearable and compact Battery powered Non-combustible and no open flame Suitable for use around people Capable of operating around a curved/circular wearable form Manufacturable at consumer-product scale Reasonable component and assembly cost Visually more spatial, irregular, and dynamic than a conventional diffused LED strip The engineer should evaluate the existing LED-based approach and credible alternatives or hybrid architectures, including where appropriate: Light guides and edge-lighting architectures Side-emitting optical fibers or similar distributed-light technologies Controlled scattering structures or materials Specialized diffusers Micro-optics, lenses, reflectors, or refractive structures Alternative light emitters Hybrid optical/electronic approaches Other technically credible non-combustible methods Required Deliverable I am purchasing a technical feasibility assessment and recommendation. The final written deliverable must answer: What are the fundamental limitations of attempting to create this type of visual effect using a conventional addressable LED strip and diffuser? Based on the product constraints, is a materially more realistic spatial and irregular spark-like illusion technically achievable? Please distinguish between what is physically achievable and what is not. What are the 2–3 most promising physical architectures for achieving the closest practical result? For each recommended architecture, explain: How it would work Expected visual improvement over the current architecture Primary technical limitations and risks Power implications Size and wearable-form-factor implications Approximate effect on component cost and manufacturing complexity Which single architecture do you recommend pursuing for the next prototype, and why? Provide a concrete next-prototype plan, including: Major components or materials to obtain What should be physically built and tested What measurements or acceptance criteria should determine success or failure What engineering expertise is needed to execute the prototype Important I have visual reference materials and prototype test videos that clearly demonstrate the desired appearance and the limitations of the current prototype. These materials will NOT be attached publicly to this job post. They may be shared privately with shortlisted candidates after confidentiality expectations are discussed and agreed upon. This is a feasibility study—not a request for someone to promise that the desired effect can be achieved. I value technically grounded conclusions, including a conclusion that certain approaches are impractical. Please do not apply if your primary expertise is only CAD modeling, general product design, firmware development, LED animation programming, or graphic/VFX design. When applying, please answer the following: Briefly describe your experience with optical engineering, illumination design, light guides, scattering, diffusers, fibers, micro-optics, or related physical lighting systems. Describe one relevant project where you improved the visual behavior or light distribution of a physical illumination system. Based only on this public description, what are the first 2–3 technical approaches you would investigate, and why? What specific information would you need from me to perform a rigorous feasibility assessment? What fixed price would you charge for the written feasibility assessment described above, and what is your estimated completion time?