Image formation method and apparatus

A recording apparatus, comprising:

• an image bearing member provided with a first area having a first image reproducing power and a second area having a second image reproducing power;
• means for forming an image on the image bearing member;
• a single detecting means for detecting the first image reproducing power of said first area of said image bearing member and the second image reproducing power of said second area of said image bearing member and for producing detection signals indicative respectively thereof;
• means for generating enabling signals indicative of when said detecting means opposes said first area and when it opposes said second area to thereby process the detection signals from said detecting means for said first and said second image reproducing powers;
• and
• control means for controlling said image forming means in dependence on the processed detection signals output from said detecting means.

An image formation apparatus for forming a visible image on a recording member, said apparatus comprising:

• an image bearing member carrying a first visible image having light and dark portions;
• a plurality of process means for forming a second visible image on the recording member in accordance with said first visible image;
• photodetecting means comprising a light emitting portion and a light receiving portion, for photoelectrically detecting the density of the first visible image on said image bearing member;
• control means for controlling said process means in accordance with an output of said photodetecting means;
• discriminating means for discriminating whether the output of said photodetecting means is within a predetermined controllable range of said control means;
• and
• interlock means for preventing the operation of said process means when the output of said photodetecting means discriminated by said discriminating means is outside said range.

An image formation apparatus for forming an image on a recording member, said apparatus comprising:

• an image bearing member carrying a first visible image having light and dark portions;
• a plurality of process means for forming a second visible image on the recording member member in accordance with the first visible image;
• photodetecting means comprising a light emitting portion and a light receiving portion, for photoelectrically detecting the density of the first visible image on said image bearing member;
• an analog-digital converter for converting an output of said photodetecting means to a digital signal;
• and
• control means having a program memory, for processing said digital signal and generating a control signal for controlling said process means, said control means holding said analog-digital converter during read-in operation of said photodetecting means, of the density of the first image, and after a predetermined period of time, releasing the operation of said analog-digital converter.

An image formation apparatus for forming a visible image on a recording member, said apparatus comprising:

• an image bearing member carrying a first visible image having light and dark portions;
• a plurality of process means for forming a second visible image on the recording member in accordance with the first visible image;
• photodetecting means comprising a light emitting portion and a light receiving portion, for photoelectrically detecting the density corresponding to the first visible image on said image bearing member;
• control means for controlling said process means in accordance with an output of said photodetecting means;
• discriminating means for discriminating whether the output of said detecting means is within a predetermined controllable range of said control means;
• and
• display means for displaying that an output of said photodetecting means is outside of said range.

An image forming apparatus for forming a visible image on a recording member, said apparatus comprising:

• an image bearing member carrying a first visible image having light and dark portions;
• a plurality of process means for forming a second visible image on the recording member in accordance with the first visible image;
• detecting means for detecting the density of said visible first image on said image bearing member;
• control means for controlling an operable condition of said process means on the basis of at least one of the output from said detecting means and a limit value;
• and
• setting means for setting the limit value for the density as detected by said detecting means, said limit value being adjustable.

An image forming apparatus for forming a visible image on a recording member, said apparatus comprising:

• an image bearing member carrying a first visible image having light and dark portions;
• a plurality of process means for forming a second visible image on the recording member in accordance with the first visible image;
• detecting means for detecting the density of the first visible image on said image bearing member;
• and
• control means for controlling an operable condition of said process means on the basis of the output from said detecting means, said control means providing limit values for the density detected by said detecting means and said limit values corresponding respectively to a light density and a dark density.

An image forming apparatus for forming a visible image on a recording member, said apparatus comprising:

• an image bearing member carrying a first visible image having light and dark portions;
• a plurality of process means for forming a second visible image on the recording member in accordance with the first visible image;
• detecting means comprising a light emitting portion and a light receiving portion, for photoelectrically detecting the density of the first visible image;
• and
• control means for holding a control signal corresponding to an output of said detecting means until the completion of a predetermined number of repeated image formations by said process means and for controlling an operable condition of said process means in accordance with the control signal held thereby.