Forensic detector and the system thereof

A system for remotely sensing a porphyrin-containing substance on a surface of an object and determining a concentration of the porphyrin-containing substance, the system comprising:

• a smartphone;
• and
• a forensic detector mountable on and communicable to the smartphone, wherein the forensic detector comprises:
• an excitation light source for generating an excitation light beam, wherein the excitation light beam has an excitation wavelength capable of exciting porphyrin to luminesce at a target wavelength centered between 665-675 nm;
• plural optical elements configured and arranged to direct the excitation light beam onto the surface and to capture an object-originated light beam coming from the surface;
• one or more sensors configured to measure a first radiation power in a first wavelength region of the object-originated light beam, and to measure one or more second radiation powers in a second wavelength region thereof, wherein the first wavelength region includes the target wavelength, and wherein the first and second wavelength regions are non-overlapping, and
• a computer processor configured to compute a signal-to-noise ratio (SNR) according to the first radiation power and a background noise power level, wherein the background noise power level is obtained from the one or more second radiation powers,
• wherein:
• the smartphone is configured to capture an image of the surface after the excitation light beam irradiates the surface;
• a porphyrin distribution map having a red pigmented region for indicating a respective region on the surface containing the porphyrin-containing substance is generated from the image;
• and
• the computing processor is further configured to use the SNR for determining the concentration of the porphyrin-containing substance.

A system for remotely sensing a porphyrin-containing substance on a surface of an object, the system comprising:

• a probe having an excitation light source and one or more sensors;
• wherein:
• the excitation light source is configured to generate an excitation light beam, wherein the excitation light beam has an excitation wavelength capable of exciting porphyrin to luminesce at a target wavelength centered between 665-675 nm;
• and
• the excitation light beam is directed onto the surface, and the one or more sensors capture an object-originated light beam coming from the surface;
• and
• a computer processor configured to execute a method for determining if the porphyrin-containing substance is present on the surface, wherein the method comprising the steps of:
• performing spectral analysis on the object-originated light beam to detect a first radiation power in a first wavelength region of the object-originated light beam, wherein the first wavelength region includes the target wavelength;
• performing spectral analysis on the object-originated light beam to detect one or more second radiation powers in a second wavelength region of the object-originated light beam, wherein the first and second wavelength regions are non-overlapping;
• and
• computing a signal-to-noise ratio (SNR) according to the first radiation power and a background noise power level, and determining if the porphyrin-containing substance is present on the surface according to the SNR, wherein the background noise power level is obtained from the one or more second radiation powers.