Patent US4234469A successfully refreshed from Google Patents.
EP0338726A2
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EP
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Image processing apparatus
Assignee: Canon Inc
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Filing: 1989-04-13
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Granted: —
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Expires: 2009-04-13
Abstract
Abstract An image processing apparatus comprises image signal input means (30), tone means (1,2,4,8) for toning the input image signal to produce a pulse width modulated signal, beam generation means (21,17) for generating a beam modulated by the pulse width modulated signal, and detection means (31) for detecting an output power of the beam generated by the beam generation means. The tone means switches an output mode of the pulse width modulated signal in accordance with the detection output of the detection means.
Inventors
- 👤 Hisashi Fukushima
- 👤 Sono Gu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 02:16
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/405; H04N1/4055; H04N1/4056
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
92 words
An image processing apparatus comprising: input means for inputting an image signal; tone means for toning the image signal input by said input means to produce a pulse width modulated signal; beam generation means for generating a beam modulated in accordance with the pulse width modulated signal supplied from said tone means; and detection means for detecting an output power of the beam generated by said beam generation means, said tone means switching an output mode of the pulse width modulated signal in accordance with the detection output of said detection means.
Claim 2
Dependent Claim
92 words
An image processing apparatus comprising: input means for inputting an image signal; tone means for toning the image signal input by said input means to produce a pulse width modulated signal; beam generation means for generating a beam modulated in accordance with the pulse width modulated signal supplied from said tone means; and detection means for detecting an output power of the beam generated by said beam generation means, said tone means switching an output mode of the pulse width modulated signal in accordance with the detection output of said detection means.
Claim 3
Dependent Claim
65 words
An image processing apparatus according to Claim 1 wherein said tone means includes a pattern generation means for generating a pattern signal having a predetermined period, D/A conversion means for converting the digital image signal input by said input means to an analog image signal, and combine means for combining the pattern signal and the analog image signal to produce the pulse width modulated signal.
Claim 4
Dependent Claim
34 words
An image processing apparatus according to Claim 2 wherein said tone means includes first control means for controlling the characteristic of the pattern signal in accordance with the detection output of said detection means.
Claim 5
Dependent Claim
40 words
An image processing apparatus according to Claim 3 wherein said pattern signal is a ramp wave signal, and said first control means controls a bias of the ramp wave signal in accordance with the detection output of said detection means.
Claim 6
Dependent Claim
36 words
An image processing apparatus according to Claim 2 wherein said tone means includes second control means for controlling a dynamic range of the analog image signal in accordance with the detection output of said detection means.
Claim 7
Dependent Claim
105 words
An image processing apparatus comprising: input means for inputting an image signal; tone means for toning the image signal input by said input means to produce a pulse width modulated signal; beam generation means for generating a beam modulated in accordance with the pulse width modulated signal supplied from said tone means; application means for generating a signal of a predetermined level independent from the image signal and applying the generated signal to said tone means; and detection means for detecting a power of the beam generated by said beam generation means when said signal of the predetermined level is applied to said tone means.
Claim 8
Dependent Claim
105 words
An image processing apparatus comprising: input means for inputting an image signal; tone means for toning the image signal input by said input means to produce a pulse width modulated signal; beam generation means for generating a beam modulated in accordance with the pulse width modulated signal supplied from said tone means; application means for generating a signal of a predetermined level independent from the image signal and applying the generated signal to said tone means; and detection means for detecting a power of the beam generated by said beam generation means when said signal of the predetermined level is applied to said tone means.
Claim 9
Dependent Claim
30 words
An image processing apparatus according to Claim 6 wherein said application means generates first and second signals of predetermined levels different from each other for application to said tone means.
Claim 10
Dependent Claim
32 words
An image processing apparatus according to Claim 7 further comprising means for switching a generation mode of the pulse width modulation signal in accordance with the detection output of said detection means.
Claim 11
Dependent Claim
65 words
An image processing apparatus according to Claim 7 wherein said tone means includes a pattern generation means for generating a pattern signal having a predetermined period, D/A conversion means for converting the digital image signal input by said input means to an analog image signal, and combine means for combining the pattern signal and the analog image signal to produce the pulse width modulated signal.
Claim 12
Dependent Claim
52 words
An image processing apparatus according to Claim 9 further comprising first control means for detecting an output power of the beam corresponding to the signal of the first predetermined level by said detection means and controlling a characteristic of the pattern signal in accordance with the detection output of said detection means.
Claim 13
Dependent Claim
40 words
An image processing apparatus according to Claim 10 wherein said pattern signal is a ramp wave signal, and said first control means controls a bias of the ramp wave signal in accordance with the detection output of said detection means.
Claim 14
Dependent Claim
54 words
An image processing apparatus according to Claim 10 further comprising record control means for detecting an output power of a beam corresponding to the signal of the second predetermined level by said detection means and controlling a dynamic range of the analog image signal in accordance with the detection output of said detection means.
Claim 15
Independent Claim
73 words
A method of calibrating a digital to pulse-width-modulated convertor in which a digital input signal is digital-to-analogue converted and the resultant analogue signal is compared with a pattern signal to produce a pulse-width-modulated signal, which method comprises the steps of inputting maximum and minimum digital signals, detecting the corresponding resultant maximum and minimum pulse-width-modulated signals and adjusting a relative attenuation and offset of the analogue and pattern signals in accordance with the detection.
Claim 16
Independent Claim
73 words
A method of calibrating a digital to pulse-width-modulated convertor in which a digital input signal is digital-to-analogue converted and the resultant analogue signal is compared with a pattern signal to produce a pulse-width-modulated signal, which method comprises the steps of inputting maximum and minimum digital signals, detecting the corresponding resultant maximum and minimum pulse-width-modulated signals and adjusting a relative attenuation and offset of the analogue and pattern signals in accordance with the detection.
References Cited (Backward Citations)
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