JP5104710B2 - Optical information reader - Google Patents

Description

The present invention includes an imaging lens and a two-dimensional optical sensor, and includes a reading mechanism for optically reading an information code attached to a reading target, and a focus switching mechanism for changing the focal position of the imaging lens. The present invention relates to an optical information reading apparatus.

A handy type optical information reading device for reading optical information such as a barcode or a two-dimensional code has a reading mechanism comprising a light receiving sensor, an imaging lens, an illumination device, etc. in a body case configured to be handheld. It is prepared for. The illumination device emits illumination light from a reading port at the front end of the main body case to a reading target (for example, a product label on which a QR code is written), and the reflected light is incident from the reading port. Via the two-dimensional optical sensor.

The optical information reading distance (distance from the reading port to the reading target) is determined in advance by the optical characteristics of the imaging optical system incorporated in the apparatus (mainly the focal length of the imaging lens). The reading operation is performed by positioning the device (reading port) at a predetermined reading distance (having a certain width) with respect to the reading target. On the other hand, in recent years, as shown in Patent Document 1, by providing a mechanism that makes the focal position of the imaging optical system variable, the range of the distance that can be read by one optical information reader is increased. The improvement of the convenience is aimed at.
JP 2000-221349 A

However, the mechanism for changing the focal position of the imaging optical system described above has a complicated structure because each of the plurality of lenses is moved along the optical axis.

The handy type optical information reading device has a shape having a reading opening having a "neck bend shape" at one end side of a vertically long, rectangular box-shaped housing so as to tilt forward in the direction of the back surface of the housing. is there. When reading optical information at a short distance with such a bend-shaped optical information reader, avoid the head of the optical information reader so that the user can align the reading port while viewing the optical information. In order to make the optical information visible, it is desirable to shift the reading range to the front position of the optical information reader. On the other hand, when reading optical information at a long distance, it is difficult to obtain a clear image with a two-dimensional optical sensor, so it is not desirable to shift the reading range. For this reason, in order to change the reading range according to the distance of the optical information, in addition to the mechanism for changing the focal position in the optical axis direction, a mechanism for changing the focal position in the vertical direction of the optical axis is required. Further, the structure becomes complicated.

SUMMARY An advantage of some aspects of the invention is that it provides an optical information reading apparatus capable of changing a focal position and an image reading range with a simple configuration.

In order to achieve the above object, claim 1 includes a two-dimensional optical sensor 28 that receives light from the imaging lens 22 including a plurality of lenses 22a, 22b, and 22c, and reads the optical information. Because
An imaging lens holder 24 for holding the imaging lens 22;
A lens holder support member 32 for supporting the imaging lens holder 24;
With
The coupling lens holder 24 is formed with a groove 34a oblique to the optical axis X1 of the two-dimensional optical sensor 28,
The lens holder support member 32 is formed with a groove 36a corresponding to the groove 34a of the imaging lens holder 24,
The imaging lens holder 24 is interposed between the groove 34 a of the imaging lens holder 24 and the groove 36 a of the lens holder support member 32 , and the imaging lens holder 24 is positioned relative to the lens holder support member 32 of the imaging lens 22. Transfer means 38 for transferring in an oblique direction with respect to the optical axis X2 ,
Further comprising
The transfer means moves the imaging lens holder 24,
The imaging lens holder 24 is close to the two-dimensional optical sensor 28, and the proximity position where the optical axis X2 of the imaging lens 22 and the optical axis X1 of the two-dimensional optical sensor 28 coincide with each other;
The imaging lens holder 24 is separated from the two-dimensional optical sensor 28, and the optical axis X2 of the imaging lens 22 and the optical axis X1 of the two-dimensional optical sensor 28 are shifted while maintaining a parallel state. It is a technical feature that it is transferred to

In the optical information reading device according to the first aspect, the imaging lens holder holds the imaging lens composed of a plurality of lenses. The imaging lens holder is close to the two-dimensional optical sensor, and the proximity position where the optical axis of the imaging lens coincides with the optical axis of the two-dimensional optical sensor, and the imaging lens holder is separated from the two-dimensional optical sensor. The imaging lens holder is spaced apart from the optical axis of the two-dimensional optical sensor and is provided at a separation position where the optical axis of the imaging lens and the optical axis of the two-dimensional optical sensor are kept parallel to each other. the direction of the groove, the transfer means interposed between the grooves corresponding to the grooves of the imaging lens holder which is provided on the lens holder support member, the imaging lens holder is transported. When reading optical information at a distance, move the imaging lens holder close to the two-dimensional optical sensor and to a proximity position where the optical axis of the imaging lens coincides with the optical axis of the two-dimensional optical sensor. Thus, the focal length of the imaging lens can be adjusted with respect to optical information at a distance away on the extension of the optical axis of the imaging lens. On the other hand, when reading optical information that is close in distance, the optical image is separated from the two-dimensional optical sensor, and the optical axis of the imaging lens and the optical axis of the two-dimensional optical sensor are shifted while maintaining a parallel state. By moving the lens holder, it is possible to cause the two-dimensional optical sensor to receive light while adjusting the focal length of the imaging lens with respect to optical information that is close to the optical axis of the two-dimensional optical sensor. Here, since the imaging lens composed of a plurality of lenses is held by the imaging lens holder, and the imaging lens is transferred integrally, the focal position and the image reading range can be changed with a simple configuration.

In the optical information reading device according to claim 2, in order to read the optical information provided on the vertical surface, when the reading port is directed in the horizontal direction, the optical information separated by moving the imaging lens holder to the close position . The focal length of the imaging lens can be adjusted with respect to. On the other hand, in order to read the optical information provided on the horizontal plane, when the reading port is directed downward, the imaging lens holder is moved to the separated position, and the focal length of the imaging lens is set with respect to the adjacent optical information. Can be matched. At this time, adjacent optical information can be read by shifting the optical axis of the imaging lens in the opposite direction from the grip portion while maintaining a state parallel to the optical axis of the two-dimensional optical sensor. For this reason, it is easy to align the reading port with the optical information.

In the optical information reading apparatus according to the third aspect, since the imaging lens holder is moved by its own weight, the moving mechanism can be configured easily.

In optical information reading apparatus according to claim 4, transfer means, between the oblique grooves provided in an imaging lens holder, a groove corresponding to the groove of the imaging lens holder which is provided on the lens holder support member Since it is composed of an interposed spherical body, it is possible to realize transfer by the weight of the imaging lens holder with a simple configuration.

In the optical information reading device according to claim 5, the groove is shallow at the end, and the resistance applied to the spherical body at the end increases and the transfer speed of the imaging lens holder decreases, so the proximity position and the separation position Thus, no impact occurs and the imaging lens holder can be smoothly transferred.

[First embodiment]
Hereinafter, an optical information reading apparatus according to a first embodiment of the present invention will be described with reference to the drawings. First, an outline of the configuration of the optical information reading apparatus 10 according to the first embodiment will be described with reference to FIGS. 1 and 2. 1 and 2 are longitudinal sectional views showing an outline of the configuration of the housing and the like of the optical information reading device 10, and FIG. 1 shows a state where a QR code Q placed on the horizontal plane H is being read. . FIG. 2 shows a state where a remote QR code Q placed on the vertical plane V is being read.

An optical information reading apparatus 10 that reads optical information such as a bar code and a QR code mainly includes a housing 12 having a vertically long, substantially rectangular box shape. The housing 12 is, for example, a molded part made of a synthetic resin such as ABS resin. One end of the housing 12 is provided with a reading port 12a having a “neck bend” so as to tilt forward toward the back surface of the housing 12, and the other end is The grip part 12H grasped by the operator is constituted. That is, the reading port 12a is provided so as to read the optical information in the oblique direction from the center line g-g of the grip portion 12H gripped by the operator, and the operator grips the grip portion 12H and opens the reading port 12a. It is made to oppose the optical information side.

An optical module 20 including an imaging lens holder 24 that integrally holds an imaging lens 22 including three lenses 22a, 22b, and 22c and a two-dimensional optical sensor 28 is accommodated inside the reading port 12a. Yes. The optical module 20 includes a lens holder support member 32 that movably holds the imaging lens holder 24, and a two-dimensional optical sensor 28 is attached to a base portion 32 </ b> A of the lens holder support member 32. An LED (light emitting diode) 46 is disposed adjacent to the optical module 20. The reading port 12 a is an opening through which incident light incident on the two-dimensional optical sensor 28 can be introduced. The light from the LED 46 is reflected by the QR code attached to the object to be read (horizontal plane H or vertical plane V) and condensed on the two-dimensional optical sensor 28 via the imaging lens 22.

A secondary battery 50 is accommodated on the other end side of the housing 12. A liquid crystal display 42 is disposed on the surface side of the housing 12 so that the operator of the optical information reading apparatus 10 can visually grasp the display contents displayed on the liquid crystal display 42. Inside the housing 12, a mounting board 40 for electronic components on which the control IC chip 44 and the like are mounted is provided.

The two-dimensional optical sensor 28 is configured so as to be able to receive the reflected light that is irradiated and reflected by the reading object R or the QR code Q through the imaging lens 22, and is, for example, a solid state such as a C-MOS or CCD. It consists of an image sensor. The imaging lens 22 functions as an imaging optical system capable of condensing incident light incident from the outside via the reading port 12 a and forming an image on the light receiving surface of the two-dimensional optical sensor 28. With the output of the image signal from the two-dimensional optical sensor 28, the control IC chip 44 decodes the optical information (QR code Q).

In the optical information reading device 10 of the first embodiment, the imaging lens holder 24 that holds the imaging lens 22 is movably held on the lens holder support member 32 as described above. The focal length of the imaging lens 22 is adjusted by moving the imaging lens holder 24 along the optical axis X 1 of the two-dimensional optical sensor 28. At the same time, the imaging lens holder 24 moves in the direction perpendicular to the optical axis X1 of the two-dimensional optical sensor 28, thereby changing the image reading range by the two-dimensional optical sensor 28.

The imaging lens holder 24 that holds the imaging lens 22 in a forward tilted state in which the reading port 12a faces downward so as to read the adjacent QR code Q placed on the horizontal plane H shown in FIG. While maintaining the state parallel to the optical axis X1 of the two-dimensional optical sensor by the mechanism, the light of the two-dimensional optical sensor 28 downward, that is, in a direction away from the two-dimensional optical sensor 28 and from the grip portion 12H to the opposite side. Move so as to deviate vertically from the axis X1.

On the other hand, the imaging lens holder 24 that holds the imaging lens 22 in the standing state in which the reading port 12a is directed to the side so as to read the far QR code Q placed on the vertical plane V shown in FIG. The imaging lens 22 is moved closest to the optical axis X1 of the two-dimensional optical sensor by a transfer mechanism described later.

The imaging lens holder 24 shown in FIG. 1 is away from the two-dimensional optical sensor 28 while maintaining a parallel state with the optical axis X1 of the two-dimensional optical sensor, and from the optical axis X1 of the two-dimensional optical sensor 28. FIG. 3A shows an enlarged view of the optical module 20 in a state of being moved so as to be displaced in the vertical direction. On the other hand, FIG. 3B shows an enlarged view of the state where the imaging lens holder 24 shown in FIG. 2 has moved so as to be closest to the imaging lens 22 on the optical axis X1 of the two-dimensional optical sensor.

As shown in FIGS. 3A and 3B, the imaging lens holder 24 is held movably in the holding chamber 32B of the lens holder support member 32. The holding chamber 32B includes a front end wall 32c having a front end hole 32g, a rear end wall 32e having a rear end hole 32h, an upper wall 32d, a bottom wall 32f, and a side wall 32j. In the optical information reading apparatus 10 of the first embodiment, as shown in FIG. 3A, in the forward tilt state (FIG. 1) with the reading port 12a facing downward so as to read the adjacent QR code Q, as shown in FIG. The lens holder 24 is transferred to a position (separated position) where it abuts on the front end wall 32c and the upper wall 32d at the front end of the holding chamber 32B. On the other hand, in an upright state (FIG. 2) with the reading port 12a facing sideways so as to read a distant QR code Q, as shown in FIG. 3 (B), the imaging lens holder 24 is positioned behind the holding chamber 32B. The rear end wall 32e and the bottom wall 32f of the end are moved to a position where they abut (close positions).

The imaging lens 22 is closest to the two-dimensional optical sensor 28 at a position where the imaging lens holder 24 shown in FIG. 3B contacts the rear end wall 32e of the rear end of the holding chamber 32B. At this time, the imaging lens holder 24 comes into contact with the bottom wall 32f, so that the optical axis X1 of the two-dimensional optical sensor 28 coincides with the optical axis X2 of the imaging lens. At this time, the distance f2 from the center of the imaging lens 22 to the two-dimensional optical sensor 28, and the distance f1 from the center of the imaging lens 22 to the reading target, with respect to the reading target at a far distance, An image is formed on the two-dimensional optical sensor 28 so that the focal point matches the distance f2 to the two-dimensional optical sensor 28.

The imaging lens 22 is farthest from the two-dimensional optical sensor 28 at a position where the imaging lens holder 24 shown in FIG. 3A contacts the front end wall 32c at the front end of the holding chamber 32B. At this time, the imaging lens holder 24 contacts the upper wall 32d, so that the optical axis X1 of the two-dimensional optical sensor 28 and the optical axis X2 of the imaging lens are shifted by a distance j, and the center of the imaging lens 22 is centered. The distance k is separated from the proximity position shown in FIG. At this time, the imaging lens 22 has a distance f2 ′ from the center of the imaging lens 22 to the two-dimensional optical sensor 28 and a distance f1 ′ from the center of the imaging lens 22 to the reading object. The focal point 22 matches the distance f2 ′ to the two-dimensional optical sensor 28, and an image is formed on the two-dimensional optical sensor 28.

In the optical information reader of the first embodiment, the imaging lens holder 24 holds the imaging lens 22 including a plurality of lenses 22a, 22b, and 22c. Then, the imaging lens holder 24 is close to the two-dimensional optical sensor 28, and the proximity position where the optical axis X2 of the imaging lens 22 coincides with the optical axis X1 of the two-dimensional optical sensor 28 (FIG. 3B). ) And the imaging lens holder 24 are separated from the two-dimensional optical sensor 28, and the optical axis X2 of the imaging lens 22 and the optical axis X1 of the two-dimensional optical sensor 28 are kept in a parallel state (FIG. 3). (A)), the imaging lens holder 24 is transferred.

When reading optical information at a distance, the optical axis X2 of the imaging lens 22 and the optical axis X1 of the two-dimensional optical sensor 28 are close to the two-dimensional optical sensor 28 as shown in FIG. The focal length of the imaging lens 22 is adjusted to the optical information separated by a distance on the extension of the optical axis X1 of the imaging lens 22 by moving the imaging lens holder 24 to a close position where the two coincide with each other. Can do. On the other hand, when reading optical information at close distances, as shown in FIG. 3A, the optical information is separated from the two-dimensional optical sensor 28, and the optical axis X2 of the imaging lens 22 and the optical axis of the two-dimensional optical sensor 28. By moving the imaging lens holder 24 to a separated position where X1 is in a parallel state while maintaining a parallel state, with respect to the optical information close to the optical axis X1 of the two-dimensional optical sensor 28, the imaging lens 22 The two-dimensional optical sensor 28 can receive light while adjusting the focal length. Here, the imaging lens 22 composed of a plurality of lenses 22a, 22b, and 22c is held by the imaging lens holder 24, and the imaging lens 22 is moved together, so that the focal position and the image reading range are changed with a simple configuration. it can.

In the optical information reading device 10 of the first embodiment, as shown in FIG. 2, when the reading port 12a is directed horizontally in order to read the QR code Q provided on the vertical surface V, the optical information reading device 10 shown in FIG. As shown, by moving the imaging lens holder 24 in the proximity direction, the focal length of the imaging lens 22 can be adjusted to the separated optical information. On the other hand, in order to read the optical information provided on the horizontal plane as shown in FIG. 1, when the reading port 12a is directed downward, the imaging lens holder 24 is moved in the separation direction as shown in FIG. In addition, the focal length of the imaging lens 22 can be adjusted to the adjacent optical information. At this time, the optical axis X2 of the imaging lens 22 is shifted in the opposite direction from the grip portion 12H while maintaining a parallel state with the optical axis X1 of the two-dimensional optical sensor 28, so that adjacent optical information can be read. it can. For this reason, it is easy to align the reading port 12a with the optical information.

In the optical information reader 10 of the first embodiment, the imaging lens holder 26 moves in the lens holder support member 32 by its own weight. The transfer mechanism for the imaging lens holder 26 will be described with reference to FIGS.
4A is a view of the optical module 20 in FIG. 3B as viewed from the direction of arrow A1, FIG. 4B is a cross-sectional view taken along line bb of FIG. 4A, and FIG. ) Is a cross-sectional view taken along the line cc in FIG. 4A, and FIG. 4D is a cross-sectional view taken along the line dd in FIG.

FIG. 4A is a view of the optical module in FIG. 3B as viewed in the direction of arrow A1, and a part of the front end wall 32c is cut away. Between the side wall 24a of the imaging lens holder 24 and the side wall 32j of the holding chamber 34B of the lens holder support member 32, a magnet plate 34 accommodated on the side wall 24a side of the imaging lens holder 24 and the holding chamber 34B are provided. A transfer mechanism including an iron plate 36 accommodated on the side wall 32j side and an iron ball 38 (transfer means) interposed between the magnet plate 34 and the iron plate 36 is disposed, and the lens holder support member 32 is moved by its own weight. It is possible. As shown in FIG. 4B, the iron ball 38 is accommodated in the guide hole 30a of the guide plate 30 disposed between the side wall 24a of the imaging lens holder 24 and the side wall 32j of the holding chamber 34B. The guide hole 30a, the magnet plate 34 accommodated in the side wall 24a of the imaging lens holder 24 as shown in FIG. 4C, and the side wall 32j of the holding chamber 34B as shown in FIG. 4D. The iron plate 36 is disposed obliquely with respect to the optical axis X1 of the two-dimensional optical sensor 28. The imaging lens holder 24 and the lens holder support member 32 are formed of a nonmagnetic material such as resin.

5A is an ee cross-sectional view of the guide hole in FIG. 4B, and FIG. 5B is a b1-b1 cross-sectional view in FIG. 5A. The magnet plate 34 is accommodated in the long hole 24m formed in the side wall 24a of the imaging lens holder 24, and the iron plate 36 is accommodated in the long hole 32m formed in the side wall 32j of the holding chamber 34B. A groove 34a for slidably holding the iron ball 38 is formed on the end surface of the magnet plate 34 on the iron plate side. Similarly, a groove 36a for slidably holding the iron ball 38 is formed on the end surface of the iron plate 36 on the magnet plate 34 side. As shown in FIG. 5B, the groove 34a of the magnet plate 34 and the groove 36a of the iron plate 36 are formed so that the central part is deep and the end part is shallow.

Here, as shown in FIG. 1, when the reading port 12a is directed downward to read the adjacent QR code, the imaging lens holder 24 comes into contact with the front end wall 32c as shown in FIG. It goes down to its own weight. On the other hand, as shown in FIG. 2, when the reading port 12a is directed to the side in order to read a distant QR code, the imaging lens holder 24 comes into contact with the rear end wall 32e as shown in FIG. Lower to its own weight. Thereby, the focal position and the image reading range are changed.

In the optical information reading device 10 of the first embodiment, it corresponds to the groove 34 a of the oblique magnet plate 34 provided in the imaging lens holder 24 and the groove 34 a of the imaging lens holder provided in the lens holder support member 32. Since the transfer mechanism composed of the groove 36a of the iron plate 36 and the iron ball 38 interposed therebetween is provided, transfer by the weight of the imaging lens holder 24 can be realized with a simple configuration. Since the imaging lens holder 24 is transferred by its own weight, the moving mechanism can be configured easily.

In the optical information reading apparatus 10 of the first embodiment, the groove 34a of the magnet plate 34 and the groove 36a of the iron plate 36 are shallow at the ends, and the resistance applied to the iron ball 38 is increased at the ends. Since the transfer speed of the image lens holder 24 is reduced, no impact occurs at the close position shown in FIG. 3B and the separated position shown in FIG. 3A, and the image lens holder 24 can be transferred smoothly. .

[Second Embodiment]
Subsequently, an optical information reading apparatus according to the second embodiment of the present invention will be described. FIG. 6 is a partial longitudinal sectional view showing an outline of the configuration of the housing and the like of the optical information reading device according to the second embodiment.
The optical information reading apparatus according to the first embodiment described above includes the box-shaped grip portion 12H. In contrast, the second embodiment is a gun-type optical information reading device 10 that includes a grip portion 12H that is independent of the main body 12B.
A reading port 12a is provided so as to read optical information in an oblique direction from the center line g-g of the grip portion 12H held by the operator, and three lenses 22a, 22b, 22c are provided inside the reading port 12a. An optical module 20 including an imaging lens holder 24 that integrally holds an imaging lens 22 made of the above and a two-dimensional optical sensor 28 is accommodated. Since the configuration of the optical module 20 is the same as that of the first embodiment described above, description thereof is omitted.

FIG. 2 is a partial vertical cross-sectional view showing an outline of the configuration of the housing and the like of the optical information reading apparatus according to the first embodiment of the present invention, and shows a state in which an adjacent QR code Q placed on a horizontal plane H is being read. 1 is a partial longitudinal sectional view showing an outline of the configuration of a housing and the like of an optical information reading apparatus according to an embodiment, and shows a state in which an adjacent QR code Q placed on a vertical plane V is being read. 3A is an explanatory diagram showing the optical module 20 in FIG. 1, and FIG. 3B is an explanatory diagram showing the optical module 20 in FIG. 4A is a view of the optical module in FIG. 3B as viewed from the direction of arrow A1, FIG. 4B is a cross-sectional view taken along line bb in FIG. 4A, and FIG. FIG. 4A is a cross-sectional view taken along the line cc in FIG. 4A, and FIG. 4D is a cross-sectional view taken along the line dd in FIG. 5A is an ee cross-sectional view of the guide hole in FIG. 4B, and FIG. 5B is a b1-b1 cross-sectional view in FIG. 5A. It is a fragmentary longitudinal cross-section which shows the structure outline | summary of the housing etc. of the optical information reader which concerns on 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical information reader 12a Reading port 12B Grip part 22 Imaging lens 24 Imaging lens holder 28 Two-dimensional optical sensor 30 Guide plate 34 Magnet plate 34a Groove 36 Iron plate 36a Groove 38 Iron ball (transfer means)
X1, X2 Optical axis

Claims (5)

An optical information reader comprising a two-dimensional optical sensor for receiving light from an imaging lens composed of a plurality of lenses, and reading optical information,
An imaging lens holder for holding the imaging lens;
A lens holder support member for supporting the imaging lens holder;
With
The coupling lens holder is formed with a groove oblique to the optical axis of the two-dimensional optical sensor,
A groove corresponding to the groove of the imaging lens holder is formed in the lens holder support member,
The imaging lens holder is interposed between the groove of the imaging lens holder and the groove of the lens holder support member , and the imaging lens holder is inclined with respect to the optical axis of the imaging lens with respect to the lens holder support member. and transfer means for transferring to,
Further comprising
The transfer means, the imaging lens holder,
The imaging lens holder is close to the two-dimensional optical sensor, and the proximity position where the optical axis of the imaging lens coincides with the optical axis of the two-dimensional optical sensor;
The imaging lens holder is separated from the two-dimensional optical sensor, and is moved to a separation position where the optical axis of the imaging lens and the optical axis of the two-dimensional optical sensor are shifted while maintaining a parallel state. An optical information reader. The optical information reading device is provided with a reading port so as to read optical information in an oblique direction from a center line of a grip portion gripped by an operator.
The transfer means includes
When the reading port is directed horizontally to read optical information provided on a vertical surface, the imaging lens holder is moved to the proximity position ,
When the reading port is directed downward in order to read optical information provided on a horizontal plane, the gripping portion is maintained while keeping the optical axis of the imaging lens parallel to the optical axis of the two-dimensional optical sensor. The optical information reader according to claim 1 , wherein the imaging lens holder is transferred to the separated position so as to be shifted in the opposite direction from the first position . The transfer means is configured to transfer the imaging lens holder to the close position when the reading port is directed in the horizontal direction in order to read optical information provided on a vertical surface , and optical provided on a horizontal plane. 3. The optical information according to claim 2 , wherein when the reading port is directed downward to read information, the imaging lens holder is transferred to the separated position by its own weight. Reader.   4. The optical information reader according to claim 3, wherein the transfer means is formed of a spherical body interposed between the groove of the imaging lens holder and the groove of the lens holder support member.   5. The optical information reader according to claim 4, wherein at least one of the groove of the imaging lens holder and the groove of the lens holder support member is formed so as to be shallow at the end.

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