Image reading apparatus with separated scanner
AssigneeKabushiki Kaisha Toshiba
InventorsHiroshi Ogasawara, Kazutoshi Shibuya, Takeshi Fuchigami
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Abstract
In an image reading apparatus used for a copying machine and a facsimile device, an image reading scanner is separated from a main device of the apparatus in order to increase the freedom of the scanning direction of the original and increase the operability of the scanner. The hand scanner is moved by a hand of an operator on the original and reads the image data line by line. The image data representing a dot pattern is transmitted to the main device as an on/off modulated optical signal through a modem. The main device receives the optical signal and demodulates the signal using a modem to reproduce the image data obtained by the hand scanner.
Claims32
An image reading apparatus comprising scanner means for reading image data of an original, and a main device for processing the image data supplied from said scanner means,
- said scanner means comprising means for emitting a polarized light in accordance with the image data, a signal component of a first polarization angle having a level higher than a signal components of other polarization angles, and
- said main device comprising:
- first receiver means for generating a first electrical signal having a level corresponding to an amount of incident light regardless of a polarization characteristic;
- an optical system in which a transmittance for a second polarizing angle is higher than a transmittance for other polarizing angles;
- second receiving means for generating a second electrical signal having a level corresponding to an amount of light transmitted through said optical system;
- means for amplifying at least one of the first and second electrical signals by first and second amplification factors such that a difference between the first and second amplification factors has a predetermined level for compensating for an attenuation amount of light transmitted through said optical system;
- and
- level difference calculating means for calculating a level difference between the first and second electrical signals upon amplification by said amplifying means.
An image reading apparatus comprising scanner means for reading image data of an original, and a main device for processing the image data supplied from said scanner means,
- said scanner means comprising means for emitting a polarized light in accordance with the image data, a signal component of a first polarization angle having a level higher than a signal components of other polarization angles, and
- said main device comprising:
- a first optical system in which a transmittance for a second polarizing angle is higher than a transmittance for other polarizing angles;
- first receiver means for generating a first electrical signal having a level corresponding to an amount of light transmitted through said first optical system;
- a second optical system in which a transmittance for the second polarizing angle differs from the transmittance for the second polarizing angle of said first optical system and a transmittance for a non-polarized light equals to the transmittance for the non-polarized light said first optical system;
- second receiving means for generating a second electrical signal having a level corresponding to an amount of light transmitted through said second optical system;
- and
- level difference calculating means for calculating a level difference between the first and second electrical signals.
An image reading apparatus comprising scanner means for reading image data of an original, and a main device for processing the image data supplied from said scanner means,
- said scanner means comprising means for emitting a polarized light in accordance with the image data, a signal component of a first polarization angle having a level higher than a signal components of other polarization angles, and
- said main device comprising:
- a first optical system in which a transmittance for a second polarizing angle is higher than a transmittance for other polarizing angles;
- first receiver means for generating a first electrical signal having a level corresponding to an amount of light transmitted through said first optical system;
- a second optical system in which a transmittance for a third polarizing angle is higher than a transmittance for other polarizing angles;
- second receiving means for generating a second electrical signal having a level corresponding to an amount of light transmitted through said second optical system;
- and
- level difference calculating means for calculating a level difference between the first and second electrical signals.
An image reading apparatus comprising scanner means for reading image data of an original, and a main device for processing the image data supplied from said scanner means,
- said scanner means comprising:
- first means for emitting a polarized light in accordance with the image data, a signal component of a first polarization angle having a level higher than a signal components of other polarization angles;
- and
- second means for emitting a polarized light in accordance with the image data, a signal component of a second polarization angle having a level higher than a signal components of other polarization angles, and
- said main device comprising:
- a first optical system in which a transmittance for a third polarizing angle is higher than a transmittance for other polarizing angles;
- first receiver means for generating a first electrical signal having a level corresponding to an amount of light transmitted through said first optical system;
- a second optical system in which a transmittance for a fourth polarizing angle is higher than a transmittance for other polarizing angles;
- second receiving means for generating a second electrical signal having a level corresponding to an amount of light transmitted through said second optical system;
- and
- level difference calculating means for calculating a level difference between the first and second electrical signals.
An image reading apparatus comprising scanner means for reading image data of an original, and a main device for processing the image data supplied from said scanner means, said main device connected to said scanner means through a wireless channel,
- said main device comprising means for returning the image data transmitted from said scanner means to said scanner means, and
- said scanner means comprising:
- means for storing the image data transmitted to said main device;
- means for comparing the image data returned from said main device and the image data stored in said storing means;
- and
- means for retransmitting the image data stored in said storing means when said comparing means detects non-coincidence of the image data.
An image reading apparatus comprising scanner means for reading image data of an original, and a main device for processing the image data supplied from said scanner means,
- said scanner means comprising:
- means for transmitting the image data with address data and an error correcting flag through a wireless channel;
- and
- means for storing the image data and the address data,
- said main device comprising:
- means for detecting a transmission error of the image data transmitted from said scanner means based on the error correcting flag;
- and
- means for transmitting a retransmission request signal to said scanner means when said detecting means detects the transmission error.
An image reading apparatus comprising scanner means for reading image data of an original, and a main device for processing the image data supplied from said scanner means,
- said scanner means comprising means for transmitting the image data after performing an error correcting coding through a wireless channel, and
- said main device comprising means for performing an error correcting decoding on the image data transmitted from said scanner means.
An image reading apparatus comprising:
- scanner means which is manually moved on an original for reading image data of the original;
- and
- a main device for processing the image data supplied from the scanner means, wherein
- said scanner means comprising means for transmitting the image data to said main device through a wireless channel, said main device comprising means for receiving the image data transmitted from said scanner means through the wireless channel, and said scanner means is connected to said main device by means of an optical communication channel.
Dependencies are inferred from the claim text.