JPH03245663A - Picture reader - Google Patents

Abstract

PURPOSE:To reduce the time up to the picture read start by controlling a fluorescent to be lighted when an interface is connected to an external device in a selection phase provided to the interface. CONSTITUTION:A personal computer 14 being an external device 9 acquiring the bus use right of an SCSI interface 8 enters the selection phase 103 to select a scanner 13 as a target. When the scanner 13 is selected, the fluorescent light 11 is preheated and then lighted. Then a command phase 104 is transited. The command phase 104 sets various parameters to the scanner 13 of the target from the personal computer 14 as an initiator. Moreover, the fluorescent light command is sent at the start of the command phase 104 and the fluorescent light 11 is immediately lighted after the command phase 104 is entered.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to SCSI (S@all Compute)
The present invention relates to an image reading device using an interface of er SystgwiInterface).

[Conventional technology]

SC3I, which was standardized by the American National Standards Institute (ANSI) in 1986, can be used for magnetic disks, magnetic tapes, optical disks,
This is a general-purpose human output interface for small and medium-sized computer systems that not only can be used commonly with various peripheral devices such as printers and scanners, but also allows communication between systems. With the progress of standardization, personal computers and minicomputers.

There is a growing momentum to adopt SC3I in various systems such as OA systems.

Up to eight host computers and peripheral devices can be connected on the SCSI bus. Various peripheral devices such as magnetic disks, magnetic tapes, printers, optical disks, image reading devices, and CD-ROMs can be connected to the SC3I bus using the same control means. Usually, the host computer is called an initiator, and the peripheral equipment is called a target, and communication between the initiator and target is the basis of the interface operation in the SC3I. Here, an initiator acquires the right to use the 5C3I bus and
This is an SC3I device that requested some kind of operation to the I device (target). In normal interface operation, the host computer is the initiator.

A target is an SCSI device that performs an operation requested by an initiator, and typically a peripheral device operates as a target.

Image reading devices also often have only the function of a target that outputs image data to an initiator, which is a host computer.

Here, the operation sequence until the image reading device communicates with the personal computer via the SCSR bus and retrieves the image will be explained.

In the operation sequence shown in Figure 5, bus free phase 1
01 is a state in which all SCSI devices are not using the bus. Next, Abitration Phase 10
Enter 2. This is a phase in which the 5C3I device acquires the right to use the bus, and a phase in which the personal computer, which is the initiator, also acquires the right to use the bus.

Next, the selection phase 103 is entered. The selection phase 103 is a phase in which the initiator (personal computer) that has acquired the right to use the bus selects an SCSI device (in this case, an image input device) to operate as a target. Next, the command phase 104 is entered. At this time, various parameters are output from the initiator to the target. Finally, a read command is sent and the data phase 105 is entered. A data phase 105 outputs image data from an image reading device as a target to a personal computer (initiator).

When the image reading device finishes outputting image data, it enters a status phase 106. In the status phase 106, the result of determining whether the output image data conforms to the parameters of the command is output as a status. Next, the message in phase 107 is entered. In this phase, the content that resulted in an error in the status phase 106 is output.

If no error occurs, bus free phase 101
The sequence ends.

Conventionally, at this time, the fluorescent lamp is preheated after the read command enters the post-manual data phase 105 in the command phase 104, and is turned on three seconds later.

Furthermore, as shown in FIG. 6, the amount of light from a fluorescent lamp fluctuates depending on the environmental temperature, so it is necessary to preliminarily turn on the light until a constant amount of light is reached, especially at low temperatures.

(Problems to be Solved by the Invention) However, as shown in FIG. 6, the amount of light of a fluorescent lamp fluctuates depending on the environmental temperature, and especially at low temperatures, preliminary lighting is required until it reaches a constant value. Furthermore, if a personal computer with a slow processing speed is used, the phases move through the abitration, selection, and command phases, but the command phase, which has many setting commands, takes a particularly long processing time. Since the fluorescent lamp was turned on in the data phase following this command phase, especially at low temperatures, after the fluorescent lamp was turned on after 3 seconds of preheating, preliminary lighting was required until the light intensity of the fluorescent lamp rose, making it difficult to read the image. It may be that it takes longer than necessary to start, even though the high-speed SC3I bus is used.

The present invention has been made to solve the problems of the conventional example as described above, and aims to provide an image reading device that can shorten the time required to start reading an image.

[Means to solve the problem]

Therefore, the present invention includes a fluorescent lamp that illuminates the document, an image sensor that receives reflected light from the document and converts it into an electrical signal, and an interface that transmits the electrical signal to an external device. , the image reading device is characterized in that it comprises a lighting control means that can preheat and turn on the fluorescent lamp by connecting with the external device through a selection phase included in the interface.

Further, the above object is achieved by providing the lighting control means with a fluorescent light command for lighting the fluorescent light at the beginning of the command phase of the interface.

[Function] With the above configuration, the image reading device according to the present invention connects to an external device from the selection phase before the data phase provided by the interface to preheat the illumination fluorescent lamp, and then Since it can be controlled to turn on, the time required to start image reading can be shortened.

Further, since a fluorescent lamp lighting command is outputted to the lighting control means at the beginning of the command phase and the fluorescent lamp can be turned on immediately after the command is inputted, the processing speed can be increased.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a control unit of an embodiment of an image reading device according to the present invention, FIG. 4A is a cross-sectional view of the image reading device of the embodiment according to the present invention, and FIG. 4B is a top view of the same. Note that the same (equivalent) components as in the conventional example shown in FIG. 5 are represented by the same reference numerals, and redundant explanation will be omitted.

In Fig. 1, 1 is a platen glass for mounting the RM, 2
3 is an image sensor (CCD) which is an imaging device that converts the image formed by the lens 2 into an electrical signal; 4 is an amplifier that amplifies the output signal of the CCD 3; 5 is an A/D (analog/digital) converter that quantizes the amplified analog image signal. 6 is a selector that selects the digital output from the A/D converter 5; 7 is an image processing circuit that processes the switching of the resolution of the digital output from the A/D converter 5 and whether it is a multi-value output or a binary output; 8 is an interface circuit of 5C3I that transmits signals with external device I9, and 10 is a CPU (central processing unit) such as a microprocessor that controls the entire image reading device (hereinafter referred to as scanner); has a built-in ROM etc. for programming. Reference numeral 11 indicates a fluorescent lamp 512 for illuminating the manuscript.
This is a fluorescent lamp control circuit that controls the In addition, A is SC
3I interface circuit 8, CPU10, and fluorescent lamp control circuit 12.

FIG. 3 shows a scanner and an external device 9 (
For example, it shows the connection status with LBP, personal computer).

Here, 13 is a scanner, 14 is a personal computer as an initiator, 15 is an LBP (laser beam printer), and 16 is a CRT (CRT display WL). Scanner 13, personal computer 14. LBP15 is connected by an SCSI bus. As shown in the figure, a scanner 13 and a personal computer 14 which is an external device 9. LBP15. CRT16
Image signals are output to the 5C5I via the interface circuit 8 of the 5C5I described above.

FIG. 4a shows the internal structure of the above-mentioned scanner 13, and the fourth
Figure b shows the document placement position of the scanner 13.

Here, 17 is a reference density object, 18 is a control unit, 19 is a CCD driver (drive circuit), 20 is a fluorescent lamp unit for illuminating an original, 21 is a reflection mirror, 22 is an original, and 23 is a platen cover.

Next, the overall operation of the embodiment of the present invention will be described with reference to FIGS. 1 to 4.

First, as shown in FIGS. 1 and 4a, the original 22 on the platen glass (original platen glass) 1 is irradiated with the fluorescent lamp 11 in the original illumination fluorescent lamp unit 20, and the reflected light from the original 22 is illuminated. is guided onto the CCD 3 by the imaging lens 2 to form an image of the document. At this time, the original 22 is placed on the platen glass 1, as shown in FIG. 4b, so that the right end becomes the leading edge of the original. Further, in FIG. 4a, the original illumination fluorescent lamp unit 20, which is a scanning optical system, has its initial value at the right end, and its initial position is confirmed by an optical position sensor (not shown). In addition, the original H4 platen glass
22, instructions for various processing modes are manually input to the scanner 13 from the personal computer 14, which is the external device 9. The instruction for this mode is, for example, a pixel density of 300 dpi (dots/inch).

200 dpi or 150 dpi (7), or whether to make the image signal binary or multilevel.

The CPU 10 receives the instructions for the various processing modes described above via the interface circuit 8 of the SCSI, and in accordance with the instructions, issues a control signal for mode switching in advance and processes the pixel density and image signal to the image processing circuit 7. Set it to .

Next, when an original reading start command is input from the personal computer 14, the CPLIIO is scanned by a motor (not shown) that drives the fluorescent lamp unit 20, and when it reaches the above-mentioned leading edge position of the original, the CPtJ 10 is
A control signal for permitting image signal output is output to the interface circuit 8 of the C5I, and the image signal read by the CCD 3 by scanning the original is sent to the personal computer 14. The number of scans of the optical system is uniquely determined by the number of pulses with which the CPLIIO drives an optical system drive motor (not shown). C
PU10 determines that reading the original is complete when the necessary number of pulses according to the size of the original is output to the motor, turns off the fluorescent lamp via the fluorescent lamp control circuit 12, and controls the disable of image signal output. A signal is output to the interface circuit 8 of the SC3I to control the reversal of the motor, and a document reading completion signal is output to the personal computer 14 via the interface circuit 8 of the SC3I.

The document illumination fluorescent lamp unit 20 moves in the direction of the arrow IA in FIG. 4a under the motor reversal control of the CPU10 described above, and the fluorescent lamp unit 20 is moved by an optical position sensor (not shown).
It is stopped when it is detected that has reached the initial position M (home position). If the next document reading start command is not received from the personal computer 14 during the return period of the optical system, the fluorescent lamp unit 20 stops at the initial position and the document reading operation ends.

Next, the operation will be explained using the SCSI phase sequence of the embodiment of the image reading apparatus according to the present invention shown in FIG. Note that sequences 101 to 102 are the same as those in the conventional example shown in FIG. 5, and therefore will be omitted.

The personal computer 14, which is the external device 9, which has acquired the right to use the bus of the 5CSI interface 8, enters a selection phase 103 for selecting the scanner 13 as a target.

Here, when the scanner 13 is selected, the fluorescent light 11
Preheat and then turn on. Next command phase 10
Enter 4. In the command phase 104, various parameters are set from the personal computer 14 as an initiator to the target scanner 13. Also, at this time, a fluorescent lamp lighting command is sent at the beginning of the command phase 104, and immediately after entering the command phase 104, the fluorescent lamp 11 is turned on.

After completing the parameter setting, the data phase 105 is entered. Here, image data is transferred from the scanner 13 to the personal computer 14.

Next, the status phase 106 is entered. The status phase 106 is a phase in which the scanner 13 sends the result of determining whether or not the image data according to the parameters set in the command phase 104 has been sent.

The message in phase 107 is a phase in which messages are received from the scanner 13, and the status phase 1
When NG is output from the scanner 13 in step 06, its contents are output. After passing through the message in phase 107, the process returns to the bus free phase 101 and the series of sequences ends.

In the above embodiment, a moving optical system was explained, but
Similarly, in the case of a device with a fixed optical system, that is, an original moving type such as a facsimile machine that moves the original, the same effect can be obtained.

(Effects of the Invention) As explained above, since the fluorescent lamp was controlled to turn on 1 at the time of connection with an external device in the selection phase provided by the interface, the fluorescent lamp was turned on in the conventional data phase. The time required to start image reading can be shortened compared to turning on the light.

Furthermore, since the fluorescent lamp lighting command is provided at the beginning of the command phase, the time required to start image reading can be similarly shortened.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a control unit of an embodiment of an image reading device according to the present invention, and FIG. 3 is an explanatory diagram showing the connection with an external device of the embodiment according to the present invention, FIG. 4a is a sectional view of the image reading device of the embodiment according to the present invention, FIG. 4b is a top view of the same, and FIG. 6 is a diagram showing the operation sequence of a conventional image reading device up to reading out an image using the SCS j bus, and FIG. 6 is a diagram showing the temperature characteristics of a fluorescent lamp. In each figure, the same reference numerals indicate the same (equivalent) components. 3... Imaging device (CCD) 8---5C5I interface circuit 9...
... External device 11 ... Fluorescent light 2.2 --- Document A --- Lighting control means

Claims (2)

[Claims] (1) comprising a fluorescent lamp that illuminates the original; an image sensor that receives reflected light from the original and converts it into an electrical signal; and an interface that transmits the electrical signal to an external device;
An image reading device characterized in that the image reading device comprises lighting control means that can preheat and turn on the fluorescent lamp by connecting with the external device through a selection phase provided by the interface. (2) The image reading device according to claim 1, wherein the lighting control means is provided with a fluorescent light command for lighting the fluorescent light at the beginning of a command phase of the interface.