Image processing system, fluorescent endoscopic illuminated imaging apparatus and imaging method

A method of forming a fluorescent image, comprising steps:

• S1:
• illuminating the inspected area with using a white light source and an excitation light source;
• respectively imaging a red light, a green light and a blue light of a reflection of a white light on a red light sensor, a green light sensor and a blue light sensor;
• using one of said red light sensor, said green light sensor and said blue light sensor to image a near infrared fluorescent light emitted from said inspected area;
• S2:
• with an image processor, determining whether said sensor imaging said near infrared fluorescent light, receives near infrared fluorescent light signals;
• if yes, proceeding to a step S3;
• if no, proceeding to a step S6;
• S3:
• with an image processor, determining whether said near infrared fluorescent light signals are received by N successive pixels;
• if yes, proceeding to a step S4;
• if no, decreasing an intensity of said white light source, and returning to said step S2, wherein N is a natural number and N≥2;
• S4:
• controlling said sensor imaging said near infrared fluorescent light, to output near infrared fluorescent light signals, and controlling the other two said sensors not to output signals;
• determining whether a contrast of said near infrared fluorescent light signal and an RGB background light achieves a predetermined value;
• if yes, proceeding to a step S5;
• if no, adjusting said intensity of said white light source, or adjusting an intensity of said excitation light source, or adjusting said intensity of said white light source and said intensity of said excitation light source at the same time, and then returning to said step S2;
• S5:
• outputting near infrared fluorescent video signals;
• S6:
• with an image processor, determining whether a reason why said near infrared fluorescent light signals are not received in said step S2 is that said inspected area does not emit said near infrared fluorescent light;
• if yes, proceeding to a step S7;
• if no, decreasing said intensity of said white light source, and returning to the step S2;
• S7:
• outputting RGB colored video signals;
• S8:
• outputting colored-fluorescent video signals according to said near infrared fluorescent video signals output in said step S5 and said RGB colored video signals output in said step S7.

An image processing system, comprising a pulse generator and an image processor, wherein said image processor includes:

• a signal conversion processor, respectively receiving intensity values of light signals received by each pixel of a red light sensor, a green light sensor and a blue light sensor, and undertaking photoelectric conversions of said light signals, wherein said red light sensor, said green light sensor and said blue light sensor respectively image a red light, a green light and a blue light of a reflection of a white light;
• one of said red light sensor, said green light sensor and said blue light sensor images a near infrared fluorescent light;
• said reflection of the white light is reflected from an inspected area illuminated by a white light source;
• said near infrared fluorescent light is emitted from said inspected area illuminated by an excitation light source;
• a signal processing processor, making a weighted average of said intensity values of light signals, which are generated by said photoelectric conversions, of two of said red light, said green light and said blue light, which are received by each pixel of two said sensors not receiving said near infrared fluorescent light, to obtain an intensity value a0 of a third light signal;
• a comparison processor, comparing an intensity value a1 with said intensity value a0, wherein a photoelectric conversion of light signals received by the pixels of said sensor receiving said near infrared fluorescent light is undertaken to obtain said intensity value a1;
• an instruction processor, receiving a comparison result from said comparison processor to make a determination and perform a corresponding operation, wherein in a case that a1>a0, if N successive pixels all satisfy a1>a0, said instruction processor sends out a first instruction to said pulse generator;
• said pulse generator controls said sensor, receiving said near infrared fluorescent light, to output near infrared fluorescent light signals and controls the other two said sensors not to output light signals;
• let a1′ be an average value of intensities of said near infrared fluorescent light signals within a given area of said sensor receiving said near infrared fluorescent light;
• if a difference between a1′ and a0 achieves a predetermined value, said instruction processor sends out a second instruction;
• if a difference between a1′ and a0 does not achieve said predetermined value, said instruction processor sends out a third instruction to decrease an intensity of said white light source;
• in said case that a1>a0, if N successive pixels do not all satisfy a1>a0, said instruction processor sends out said third instruction to decrease said intensity of said white light source;
• if a difference between a1′ and a0 does not achieve said predetermined value, said instruction processor sends out a fourth instruction to increase or decrease said intensity of said white light source;
• in a case that a1<a0, said instruction processor sends out said third instruction to decrease said intensity of said white light source;
• in a case that a1=a0, said instruction processor sends out said third instruction to decrease said intensity of said white light source, and compare an intensity value all with said intensity value a0, wherein the photoelectric conversion of light signals received by the pixels of said sensor receiving said near infrared fluorescent light is undertaken after decreasing said intensity of said white light source to obtain said intensity value all;
• if a11<a0, said instruction processor sends out a fifth instruction to restore said intensity of said white light source to a value of said intensity of said white light used before said intensity of said white light is decreased, and sends out said second instruction to said pulse generator to control said red light sensor, said green light sensor and said blue light sensor to respectively output a red light signal, a green light signal and a blue light signal under a condition that said intensity of said white light source has been restored;
• a signal output processor, receiving said second instruction and outputting colored-fluorescent video signals according to said near infrared fluorescent signal output by said sensor receiving said near infrared fluorescent light, said red light signal, said green light signal and said blue light signal output by said red light sensor, said green light sensor and said blue light sensor.