Device for converting analog signals from a natural leaf scanner into digital signals and method of operating same

A device for converting a succession of analog voltage signals representative of the light intensity of light from and controlled by a corresponding succession of finite surface locations of a natural leaf into a white, black or gray digital signal for each given location, said device comprising:

• means for creating a white digital signal when an analog voltage signal at a given location exceeds a first threshold voltage corresponding to a given light intensity value;
• means for creating a black digital signal when an analog voltage signal at a given location is below a second threshold voltage;
• averaging means for creating said second threshold voltage by averaging at least a majority of previous analog signals of said succession of locations;
• means for excluding said analog signal for a given location from said averaging means when said analog signal creates said black digital signal;
• and, means for creating a gray digital signal in the absence of said white and black signals for a given location.

A device for converting a succession of analog voltage signals representative of the light intensity of light from and controlled by a corresponding succession of finite surface locations of a natural leaf into a white, black or gray digital signal for each given location, said device comprising:

• means for creating a white digital signal when an analog voltage signal at a given location exceeds a threshold voltage corresponding to a given light intensity value;
• averaging means for creating a substantially continuously updated datum voltage by averaging at least a majority of previous analog signals of said succession of locations;
• means for reducing said datum voltage to an offset datum voltage;
• means for comparing said analog signal for a given location with said offset datum voltage;
• means for creating a black digital signal when said analog signal for said given location is less than said offset datum voltage;
• means for creating a gray digital signal in the absence of said white and black signals for a given location;
• means for excluding said analog signal for a given location from said averaging means when said analog signal creates said white digital signal;
• and, means for amplifying said analog voltage signal and said averaging means and black signal creating means being operative on said amplified analog signal.

A device for converting a succession of analog voltage signals representative of the light intensity of light from and controlled by a corresponding succession of finite surface locations of a natural leaf into a white, black or gray digital signal for each given location, said device comprising:

• means for creating a white digital signal when an analog voltage signal at a given location exceeds a threshold voltage corresponding to a given light intensity value;
• averaging means for creating a substantially continuously updated datum voltage by averaging at least a majority of previous analog signals of said succession of locations;
• means for reducing said datum voltage to an offset datum voltage;
• means for comparing said analog signal for a given location with said offset datum voltage;
• means for creating a black digital signal when said analog signal for said given location is less than said offset datum voltage;
• means for creating a gray digital signal in the absence of said white and black signals for a given location;
• means for excluding said analog signal for a given location from said averaging means when said analog signal creates said black digital signal;
• and, means for amplifying said analog voltage signal and said averaging means and black signal creating means being operative on said amplified analog signal.

A device for converting a succession of analog voltage signals representative of the light intensity of light from and controlled by a corresponding succession of finite surface locations of a natural leaf into a white, black or gray digital signal for each given location, said device comprising:

• means for creating a white digital signal when an analog voltage signal at a given location exceeds a thrreshold voltage corresponding to a given light intensity value;
• averaging means for creating a substantially continuously updated datum voltage by averaging at least a majority of previous analog signals of said succession of locations;
• means for reducing said datum voltage to an offset datum voltage;
• means for comparing said analog signal for a given location with said offset datum voltage;
• means for creating a black digital signal when said analog signal for said given location is less than said offset datum voltage;
• means for creating a gray digital signal in the absence of said white and black signals for a given location;
• and, means for excluding said analog signal for a given location from said averaging means when said analog signal creates said white digital signal.

A device for converting a succession of analog voltage signals representative of the light intensity of light from and controlled by a corresponding succession of finite surface locations of a natural leaf into a white, black or gray digital signal for each given location, said device comprising:

• means for creating a white digital signal when an analog voltage signal at a given location exceeds a threshold voltage corresponding to a given light intensity value;
• averaging means for creating a substantially continuously updated datum voltage by averaging at least a majority of previous analog signals of said succession of locations;
• means for reducing said datum voltage to an offset datum voltage;
• means for comparing said analog signal for a given location with said offset datum voltage;
• means for creating a black digital signal when said analog signal for said given location is less than said offset datum voltage;
• means for creating a gray digital signal in the absence of said white and black signals for a given location;
• and, means for excluding said analog signal for a given location from said averaging means when said analog signal creates said black digital signal.

A method for converting a succession of analog voltage signals representative of the light intensity of light from and controlled by a corresponding succession of finite surface locations of a natural leaf into a white, black or gray signal for each given location, said method comprising the steps of;

• (a) creating a white digital signal when an analog voltage signal at a given location exceeds a threshold voltage corresponding to a given light intensity value;
• (b) creating a substantially continuously updated datum voltage by averaging at least a majority of previous analog signals of said succession of locations;
• (c) reducing said datum voltage to an offset datum voltage;
• (d) comparing at least the analog signal for a given location which does not exceed said threshold voltage with said offset datum voltage;
• (e) creating a black digital signal when said analog signal for a given location is less than said offset datum voltage;
• (f) creating a gray digital signal in the absence of said white and black signals for a given location;
• and
• (g) excluding said analog signal for a given location from said datum voltage creating step when said analog signal exceeds said threshold voltage.