Patent Application
20210256329
The present invention relates to an information processing apparatus and a method of extracting a recording medium.
It is known that a recording apparatus performs recording by using control parameters corresponding to a type of a recording medium. Japanese Patent Laid-Open No. 2016-215591 discusses that, to perform recording by using appropriate control parameters, a plurality of characteristic values of a recording medium to be recorded is measured, and a type of the recording medium is determined by comparing the characteristic values with reference values.
The present invention provides an information processing apparatus, comprising: an acquisition unit configured to acquire the measurement results obtained by a measurement unit measuring a characteristic of a recording medium set to be measurable by the measurement unit a plurality of times; a storage unit configured to store extraction ranges set to respective types of recording media for determination of a type of a recording medium; an input unit configured to input information corresponding to a type of the recording medium whose the measurement results of which are acquired by the acquisition unit; a setting unit configured to set, based on the plurality of measurement results which is obtained by the measurement unit measuring the characteristic of the recording medium a plurality of times and acquired by the acquisition unit, and the type of the recording medium indicated by the information input by the input unit, a parameter for correcting the measurement results to reduce difference between the measurement results and the extraction range of the type of the recording medium indicated by the information; and an extraction unit configured to correct, by using the parameter, measurement results obtained by the measurement unit measuring a characteristic of a recording medium to be recorded by a recording unit, and to extract a candidate type of the recording medium, the measurement results of which are acquired by the acquisition unit, based on the corrected measurement result and the extraction range.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. Each of the embodiments of the present invention described below can be implemented solely or as a combination of a plurality of the embodiments. Also, features from different embodiments can be combined where necessary or where the combination of elements or features from individual embodiments in a single embodiment is beneficial.
In the technique discussed in Japanese Patent Laid-Open No. 2016-215591, an error of a sensor measuring characteristic values of a recording medium, differences among recording media, different measurement environments, and the like have an influence on the measurement values. Therefore, in a case where previously prepared reference values are used, the type of a recording medium may not be determined with sufficient accuracy.
The present exemplary embodiment is directed to determination of the type of a recording medium with high accuracy.
An input/output unit 406 is provided on an upper part of the recording apparatus 100. The input/output unit 406 is an operation panel, and can display an ink residual amount and a candidate type of a recording medium on a display thereof. The user can select a type of a recording medium and make recording settings by using operating keys.
The carriage 101 includes an optical sensor 201 (
The recording medium 105 such as a roll sheet is conveyed on a platen 106 in the Y direction by a conveyance roller (not illustrated). The recording operation is performed in such a manner that ink drops are ejected from the recording head 102 while the carriage 101 moves in the X direction on the recording medium 105 conveyed on the platen 106 by the conveyance roller. When the carriage 101 moves to an end of a recording area on the recording medium 105, the conveyance roller conveys the recording medium 105 by a certain amount, and moves an area where a next recording scan is performed to a position recordable by the recording head 102. The image is recorded by repeating the above-described operation.
The second LED 302 is a light source having an irradiation angle of 60 degrees in the Z direction to the surface (measurement surface) of the recording medium 105. The first photodiode 304 receives the light that has been emitted from the second LED 302 and reflected by the recording medium 105 at an angle of 60 degrees in the Z direction. That is, the angle of the light emission and the angle of the light reception become equal to each other, and the first photodiode 304 forms an optical system that detects a specular reflection component of the light reflected from the recording medium 105.
The third LED 303 is a light source having an irradiation angle of the normal line (90 degrees) to the surface (measurement surface) of the recording medium 105. The second photodiode 305 and the third photodiode 306 each receive light that has been emitted from the third LED 303 and reflected by the recording medium 105. The second photodiode 305 and the third photodiode 306 each measure a distance between the optical sensor 201 and the recording medium 105 based on a light receiving quantity that changes depending on the distance between the optical sensor 201 and the recording medium 105.
Although, in the present exemplary embodiment, the optical sensor 201 is installed in the carriage 101, the installation position is not limited thereto. For example, the optical sensor 201 may be fixed to and installed in the recording apparatus 100. Alternatively, the optical sensor 201 may be a measurement device, separately from the recording apparatus, that measures a diffused reflection characteristic value and a specular reflection characteristic value of the recording medium and then transmits the measured characteristic values to the recording apparatus.
An interface (I/F) circuit 410 connects the recording apparatus 100 and a network such as an external local area network (LAN). The recording apparatus 100 transmits and receives various kinds of jobs, data, etc. to and from an apparatus such as an external host computer via the I/F circuit 410.
The input/output unit 406 includes an input unit and an output unit. The input unit receives an instruction to turn on a power supply, an instruction to perform recording, and an instruction to set various kinds of functions from a user. The output unit displays various kinds of apparatus information such as a power saving mode, and a setting screen for various kinds of functions performable by the recording apparatus 100. In the present exemplary embodiment, the input/output unit 406 is an operation panel provided in the recording apparatus 100. The input/output unit 406 is connected to a system bus 416 via an input/output control circuit 405 such that transmission/reception of data is possible. In the present exemplary embodiment, the CPU 401 controls information notification performed by the output unit.
In addition, the input unit may be a keyboard of the external host computer, and may receive a user instruction from the external host computer. The output unit may be an LED display, a liquid crystal display (LCD) display, or a display connected to the host apparatus. In a case where the input/output unit 406 is a touch panel, a user instruction can be received via software keys. Further, the input/output unit 406 may include a speaker and a microphone, and may receive input from a user by voice and perform notification to the user by voice.
An information processing apparatus that includes a CPU and a ROM having functions similar to the functions of the CPU 401 and the ROM 402 and is externally connected to the recording apparatus 100 may perform recording medium determination processing to be described below to determine the recording medium to be used in the recording apparatus 100.
In a case where the measurement by the optical sensor 201 is performed, an LED control circuit 407 is driven by the CPU 401, and a predetermined LED inside the optical sensor 201 is controlled to emit light. Each of the photodiodes of the optical sensor 201 outputs a signal corresponding to the received light, the signal is converted into a digital signal by an analog-to-digital (A/D) conversion circuit 408, and the digital signal is temporarily stored in the RAM 403. The data to be held even when the power supply of the recording apparatus 100 is turned off is stored in the EEPROM 404.
A recording head control circuit 411 supplies a driving signal corresponding to recording data to a nozzle driving circuit that is mounted on the recording head 102 and includes a selector and a switch, thereby controlling recording operation of the recording head 102, for example, a driving order of the nozzles. For example, in a case where data to be recorded is transmitted from outside to the I/F circuit 410, the data to be recorded is temporarily stored in the RAM 403. The recording head control circuit 411 drives the recording head 102 based on recording data converted from the data to be recorded. At this time, a line feed (LF) motor driving circuit 412 drives an LF motor 413 based on a bandwidth, etc. of the recording data, and the conveyance roller connected to the LF motor 413 is rotated to convey the recording medium. A carriage (CR) motor driving circuit 414 drives the CR motor 415 to cause the carriage 101 to perform scanning via the carriage belt 103.
The data transmitted from the I/F circuit 410 includes not only the data to be recorded but also data of content set by a printer driver. Further, for example, the data to be recorded may be received from outside via the I/F circuit 410 and stored in a storage unit, or may be previously stored in the storage unit such as a hard disk. The CPU 401 reads out image data from the storage unit and controls an image processing circuit 409 to convert the image data into the recording data (binarization processing) for use of the recording head 102. The image processing circuit 409 performs various image processing such as color space conversion, horizontal-vertical (HV) conversion, gamma correction, and rotation of the image, in addition to the binarization processing.
In the present exemplary embodiment, a diffused reflection value and a specular reflection value are measured as characteristics of the recording medium by the optical sensor 201, and a type of the recording medium to be recorded is determined based on the measurement results and the characteristic extraction range stored in the EEPROM 404. The diffused reflection value corresponds to whiteness of the recording medium, and the specular reflection value corresponds to glossiness of the recording medium.
When values obtained by measuring the characteristics of each of the recording media a plurality of times are mapped in two-dimensional coordinate axes, a diagram of
The measurement value of the same recording medium, however, is varied in each apparatus depending on individual difference, minute difference in attachment position, etc. of the optical sensor 201. In a case where the measurement value is out of the extraction range of the type of the recording medium to be recorded previously stored in the EEPROM 404, the apparatus cannot determine the current type of the recording medium to be recorded, which deteriorates determination accuracy of the type of the recording medium.
On the other hand, the positional relationship among the measurement value groups does not depend on the apparatus, and maintains an arrangement similar to the arrangement in
Upon receiving an instruction to start sheet feeding from the user via the operation panel, i.e., the input/output unit 406, the CPU 401 performs processing to feed the recording medium 105.
When the sheet feeding is started, the recording medium 105 is conveyed, by the conveyance roller, to a position on the platen 106 where the optical sensor 201 can detect the recording medium 105. When the recording medium 105 is conveyed, the carriage 101 moves on the recording medium 105 in the X direction, and, in step S501, the optical sensor 201 acquires the diffused reflection value and the specular reflection value of the recording medium 105. The characteristics of the recording medium may be measured at one position, or measurement results obtained at a plurality of positions may be averaged. Further, the characteristics may be measured while the optical sensor 201 is in a stationary state or while the optical sensor 201 moves. The measurement values are temporarily stored in the memory such as the RAM 403.
Next, in step S502, the CPU 401 reads out the acquired measurement values from the memory, and corrects the measurement values by the correction expression. The correction expression calculation processing will be described in detail below.
In step S503, the measurement values corrected in step S502 and the extraction range stored in the EEPROM 404 are compared to extract the type of the recording medium corresponding to the recording medium 105. In this step, CPU 401 functions as an extraction means. Although the type of the recording medium, of which the measurement values are included in the extraction range, is extracted, some of the extraction ranges stored in the EEPROM 404 overlap with the extraction range of the other type of the recording medium as illustrated in
In step S504, it is determined whether the type of the recording medium extracted in step S503 is present. In a case where the extracted type of the recording medium is present (YES in step S504), the processing proceeds to step S505. In step S505, as illustrated in
In a case where the extracted type of the recording medium is not present in step S504 (NO in step S504), then in step S506, an item “all” for displaying all categories and all sheet types at a time is displayed on the operation panel as illustrated in
In a case where the user selects the type of the recording medium using the input/output unit 406 in step S507 (YES in step S507), the processing proceeds to step S508.
In step S508, as illustrated in
The type of the fed recording medium 105 is determined in the above-described manner. In the processing of the flowchart in
Next, the processing for calculating the correction expression correcting the measurement values in step S502 of
The correction expression calculation processing is started when the user selects an item “automatic determination correction” on the input/output unit 406. The item “automatic determination correction” is displayed in the following manner.
First, a home screen (
When the item “main body setting” is selected on the home screen, a main body setting screen as illustrated in
When the correction expression calculation processing is started, the sheet feeding is performed to convey the recording medium 105 to the position where the optical sensor 201 can detect the recording medium 105 on the platen 106. In a case where the sheet feeding has been already completed, the sheet feeding processing is not performed.
When the recording medium 105 is placed on the platen 106, in step S801, the categories and the item “all” are displayed on the input/output unit 406 as illustrated in
Next, in step S802, the user selects the type of the recording medium on the input/output unit 406 (YES in step S802), the processing proceeds to step S803. Here, a case where “backlight film HG” is selected will be described as an example.
In step S803, the optical sensor 201 measures the plurality of diffused reflection values and the plurality of specular reflection values as the characteristics of the recording medium 105, and CPU 401 temporarily stores these values in the RAM 403. In this step, CPU 401 functions as an acquisition unit. In the present exemplary embodiment, 100 points on the recording medium 105 are measured to acquire the measurement values. The 100 points are points at different positions on the recording medium 105.
In step S804, the extraction range of the type of the recording medium selected in step S802 is acquired from the EEPROM 404.
Subsequently, in step S805, the correction expression is calculated. Specifically, the measurement values acquired in step S803 and the extraction range acquired in step S804 are compared. The comparison in the present exemplary embodiment is realized by performing overlapping processing of an extraction range of a specific recording medium.
First, a method of calculating the amount of translation will be described. A difference between a center point 1011 of the rectangle 1001 and a center point 1012 of the rectangle 1002 is calculated as the amount of translation. The calculation is one-dimensionally performed along each of the axes. For example, the amount of translation on a diffused reflection axis corresponds to an amount b in
Next, a method of calculating the scaling factor will be described. In the present exemplary embodiment, the scaling is performed while an aspect ratio of the rectangle 1002 is maintained. A scaling factor a of the rectangle 1002 is calculated by the following expression.
a=(Q+R)/(O+P)
O: a length of the rectangle 1002 in a lateral direction
P: a length of the rectangle 1002 in a vertical direction
Q: a length of the rectangle 1001 in the lateral direction
R: a length of the rectangle 1001 in the vertical direction
For example, in a case where the length O of the rectangle 1002 in the lateral direction is 1, the scaling factor of the diffused reflection can be obtained by a length Oa of the rectangle 1003 in the lateral direction.
Accordingly, the correction expression for correcting the measurement values is summarized as follows.
y1=a x1+b (1)
y1: the diffused reflection value of the measurement values after the correction
a: the scaling factor of the rectangle
x1: the diffused reflection value obtained by actual measurement
b: the amount of translation
In the similar manner, the amount of translation on the specular reflection axis corresponds to an amount c in
y2=a x2+c (2)
y2: the specular reflection value of the measurement value after the correction
a: the scaling factor of the rectangle
x2: the specular reflection value obtained by actual measurement
c: the amount of translation
Note that the scaling factor a in each of the expression (1) and the expression (2) can be accurate when a distance from a position of the diffused reflection value x1 and a position of the specular reflection value x2 on the coordinates to a centroid of the corresponding rectangle where each position belongs to are considered; however, an approximated value is used in the present exemplary embodiment. This is because the amount of translation can contribute largely to the overlapping of the rectangles as compared with the scaling factor.
In other words, as illustrated in
In a case where the apparatus is different, i.e., in a case where the recording apparatus is different in the present exemplary embodiment, there are the number of factors, including the measurement condition, that influence the measurement values, and the influence is large. In
In contrast, the scaling factor a is about 80% to about 120% in percentage, and the correction amount of the measurement value by the scaling factor a is considerably smaller than the correction amount by the translation. The size of the rectangle 1002 is influenced by variation of the measurement values. In the plurality of times of measurement, the measurement is performed under the same condition except different measurement positions on the recording medium, and the measurement values by the plurality of times of measurement tend to be concentrated in a close range.
In the present exemplary embodiment, as an example of the difference in the measurement value between the different apparatuses, the correction value of the specular reflection value in
In this example, the comparison is performed by using the rectangles illustrated in
Further, in the present exemplary embodiment, the rectangle 1003 is used only for calculation of the correction expression, and the extraction range used in the recording medium extraction processing in step S503 in the recording medium type determination processing in
In step S806, the correction expression calculated in step S805 is stored in the EEPROM 404. In steps S805 and S806, CPU 401 functions as a setting unit. The above-described correction expression can be calculated from at least one type of a recording medium. Even in a case of a type of a recording medium not supplied to the recording apparatus before, applying the calculated correction expression makes it possible to improve the extraction accuracy as compared with a case where the correction expression is not applied. To perform determination with higher accuracy, however, it is desirable to calculate the correction expression for each of three or more types of recording media. In this case, the above-described overlapping processing is performed on each of the types of recording media, and obtained results are averaged. For example, in a case where the correction expression is calculated for each of three types of recording media 1 to 3, the obtained calculation results are expressed by the following three expressions.
y=a1x+b1
y=a2x+b2
y=a3x+b3
A final correction expression calculated by averaging the three results obtained based on the three expressions is as follows.
y=((a1+a2+a3)/3)x+(b1+b2+b3)/3
The processing in
In the present exemplary embodiment, the correction expression calculation processing in
As described above, if the extraction range common to all apparatuses is previously stored and displacement between measurement values and the extraction range is corrected, displacement specific to each apparatus can be corrected, and the type of the recording medium can be determined. This makes it possible to improve the determination accuracy.
In the first exemplary embodiment, the displacement between the measurement values and the extraction range is corrected by the correction expression for correcting the measurement values. In a second exemplary embodiment, the displacement between the measurement values and the extraction range is corrected by correcting the extraction range. Descriptions of parts similar to the parts in the first exemplary embodiment will be omitted.
The correction of the extraction range will be described. To change the extraction range based on the displacing amount, the translation and the scaling of the rectangle 1001 in
u: a value of the extraction range before conversion
a: the scaling factor of the rectangle
t: a value of the extraction range after the conversion
b: the amount of translation
A value at each of four corners of the extraction range after the conversion is obtained by substituting a value at each of the four corners of the extraction range before the conversion for tin the expression. The extraction range stored in the EEPROM 404 is updated with the obtained value. The update is performed on all of the extraction ranges stored in the EEPROM 404.
In the present exemplary embodiment, the recording medium type determination processing is performed after the extraction ranges stored in the EEPROM 404 is updated. Therefore, the processing in step S502 of
Correcting the extraction range in the above-described manner also makes it possible to correct the displacement between the measurement values and the extraction range.
In the above-described exemplary embodiments, all of the types of recording media, the extraction ranges of which are previously stored in the EEPROM 404, are determination targets in the recording medium type determination processing. However, some of the recording media may not be used by the user. In a case where the extraction range of an unused recording medium and the extraction range of a used recording medium are close to each other, the unused recording medium may be extracted in the recording medium type determination processing. In the third exemplary embodiment, among the recording media of which the extraction ranges are previously stored in the EEPROM 404, a recording medium often used by the user can be selected and set as the determination target in the recording medium type determination processing. Descriptions of parts similar to the parts in the first exemplary embodiment are omitted.
In step S503 in the recording medium type determination processing in
The same correction expression is used even after the recording medium to be determined is switched.
As described above, selecting the type of a recording medium to be determined in the recording medium type determination processing increases the possibility that the type of a recording medium that the user wants to select is extracted.
In the above-described exemplary embodiments, a specular reflection value and a diffused reflection value are acquired as characteristics, and the type of a recording medium is extracted based on the acquired measurement values. Characteristics to be acquired, however, are not limited thereto. For example, the recording apparatus may include a sensor for measuring a thickness of the recording medium, and may acquire the thickness of the recording medium as a characteristic. In addition, the number of characteristics to be acquired is not limited to two. Increasing the number of acquired characteristics facilitates determination of the types of recording media having close two-dimensional characteristics, which makes it possible to further improve the determination accuracy.
According to the above-described exemplary embodiments, it is possible to determine the type of a recording medium with high accuracy.
Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.
This application claims the benefit of Japanese Patent Application No. 2020-026533, filed Feb. 19, 2020, which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-026533 | Feb 2020 | JP | national |
