Smartphone incorporated on-site crude oil analyzer based on CMOS image sensor

Abstract

Crude oil is a mixture composed of various hydrocarbons such as saturated hydrocarbons, unsaturated hydrocarbons, resins, and asphaltenes. Among them, the unsaturated hydrocarbons consist of alkenes, alkynes, and aromatic hydrocarbons, andthe aromatic hydrocarbons contain chemicals with one or more benzene rings, which emit fluorescence upon receiving an ultraviolet light. Conventional instrument for detecting the emitted fluorescence from the crude oil usually utilize an expensive light source, e.g., halogen lamp, and an expensive detector, e.g., photomultiplier tube (PMT), to measure the intensity of the emitted fluorescence and to quantify the crude oil concentration. While this established instrument can provide high sensitivity with a high-end detector, i.e., PMT, this relatively expensive, bulky, and single pixel detector has many limitations to be widely accepted in on-site instruments. To address this issue, we propose a crude oil fluorescence analyzer composed of low-cost and compact optoelectronic elements, i.e., light emitting device (LED) for light source and complementary metal oxide semiconductor (CMOS) image sensor for detector. Since this device employs multi-million pixels of CMOS image sensor, it can minimize the fluorescent noise by selective data collection, enabling low concentration (~ 1 ppb) crude oil fluorescence detection as an on-site platform.