Multi-function monitoring module for a printer

• US 6,419,342 B1
• Filed: 09/25/2000
• Issued: 07/16/2002
• Est. Priority Date: 11/19/1999
• Status: Expired due to Fees

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Lindenhovius, Karianne H., Bronswijk, Tako K. A. M., Timmers, Wilhelmus A. G.
• Primary Examiner(s): Hilten, John S.
• Assistant Examiner(s): Stewart, Jr., Charles W.
• Application Number:
  US09/668,540
• Time in Patent Office: 659 Days
• Field of Search: 347/19, 347/14, 347/10, 347/12, 347/11, 347/23, 347/37, 347/15, 347/43, 347/41
• US Class Current: 347/19
• CPC Class Codes: B41J 2/2135 Alignment of dots
• CPC Class Codes: B41J 29/393 Devices for controlling or analysing the entire machine ; Controlling or analysing mechanical parameters involving printing of test patterns
• CPC Class Codes: H04N 1/00002 Diagnosis, testing or measuring; Detecting, analysing or monitoring not otherwise provided for error detection, error correction or monitoring in digital computers or digital computer components G06F11/00
• CPC Class Codes: H04N 1/00015 Reproducing apparatus
• CPC Class Codes: H04N 1/00031 Testing, i.e. determining the result of a trial H04N1/00029 takes precedence; using test signals for transmission mode changing H04N2201/33371
• CPC Class Codes: H04N 1/00045 using a reference pattern designed for the purpose, e.g. a test chart
• CPC Class Codes: H04N 1/00082 Adjusting or controlling interrupting an operation H04N1/00915; inhibiting an operation H04N1/00925

Abstract

In a module for monitoring the print quality of a dot printer (10), comprising a radiation source (41), a condensor lens system (43′) for forming an illuminated area (45) on a printing medium (13) and an imaging lens system (87,89) for imaging the illuminated area on a detector (49′), the detector comprises at least a linear array of detector elements and the imaging system is configured in such a way that both the illuminated area and a small portion thereof can be imaged. This allows detection of both the gray scale of a print line (35) and the size and colour of an individual dot. A dot printer provided with this modules gives an improved print quality.

Claims

1. A method of printing information in the form of dots on a printing medium, comprising the steps of:

supplying the information to be printed to a dot printer;

printing a test pattern on the medium;

optically detecting the test pattern;

comparing the test pattern with a reference;

adapting printer settings if a deviation between the test pattern and the reference is detected, and

printing the information supplied to the printer,

characterized in that the step of detecting the test pattern comprises detecting the gray scale of a test print line and detecting the size of at least one individual test dot.

2. A method as claimed in claim 1, characterized in that the step of detecting the test pattern also comprises detecting the colour of a test dot.

3. A method as claimed in claim 1, characterized in that the step of printing a test pattern comprises printing a first portion of the information to be printed.

4. A method as claimed in claim 1, characterized in that a test dot and a portion of a test print line are detected simultaneously.

5. A method as claimed in claim 1, characterized in that a test dot and a portion of a test print line are detected sequentially.