Verification of a high precision CMOS sensor for angle-of-arrival (AOA) measurement of LED light in ultra-miniaturized applications

• Published in: Integration (Amsterdam) Vol. 75; pp. 1 - 10
• Main Authors: Feiler, André, Veit, Dominik, Straczek, Lukas, Oehm, Jürgen
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.11.2020; Elsevier BV
• Subjects: Angle-of-arrival (AOA); CMOS; CMOS sensor; High precision; Illumination; Lens-less optical measurement; Light angle incidence measurement; Light emitting diodes; Light sources; Measurement; Mechanical components; Mechanical properties; Noise intensity; Power consumption; Sensors; Ultra-miniaturization; Angle-of-arrival (AOA); Ultra-miniaturization; CMOS sensor; Light angle incidence measurement; Lens-less optical measurement; High precision
• ISSN: 0167-9260; 1872-7522
• DOI: 10.1016/j.vlsi.2020.05.009

In this study a specially revised version of the concept for measuring the angle-of-arrival (AOA) of incidence light was used, which is particularly well suited for the construction of trigonometric sensor concepts with external dimensions of only a few millimeters. The aim of the study was to break down the interrelationships for the overall systemically achievable accuracies. The study therefore focused on the lowest possible power consumption of the LED light source used, minimum component dimensions and quantities, outline of the practicable minimum distances between LED light source and integrated sensor unit, robustness of the sensor against gradients and intensity changes in lighting, illumination intensity and sensor noise, as well as the requirements for the precision of the mechanical components used. It could be shown that the key limiting factor isn't the optical/electronic precision of the CMOS sensor concept used, but the finite precision of the mechanical components. •A high precision light angle measurement for ultra miniaturized applications was designed.•Errors due to illumination gradients were investigated, evaluated and compensated.•The measurement principle reaches up to 16 bits of maximum measurement resolution.•The measuring principle can be extended on a vast majority of optical measurements.•Measurements without lenses, reflectors or lighting arrays are possible.