WO2019022153A1

WO2019022153A1 - Optical information reading device and method for manufacturing optical information reading device

Info

Publication number: WO2019022153A1
Application number: PCT/JP2018/027939
Authority: WO
Inventors: 伊藤　誠; 亮杉浦
Original assignee: 株式会社デンソーウェーブ
Priority date: 2017-07-28
Filing date: 2018-07-25
Publication date: 2019-01-31

Abstract

An optical information reading device (10) is provided with an image-forming lens (25), and a lens-holding part (60) assembled to a holder (50) in a state in which the image-forming lens (25) is held in place. A flange undersurface (63) and end surfaces (61a, 61b) are provided to the lens-holding part (60) as reference planes along the optical axis (L1) of the image-forming lens (25). In the holder (50), the flange undersurface (63) and the and surfaces (61a, 61b) come in contact face-to-face when the lens-holding part (60) is assembled such that the light that has passed through the image-forming lens (25) forms an image on an area sensor (23), and an upper surface (54) and edge surfaces (56a, 56b) of an opening (55) are formed as guide surfaces with which the flange undersurface (63) and the end surfaces (61a, 61b) make sliding contact when the lens-holding part (60) is moved so as to follow the optical axis (L). This suppresses the influence of a one-sided blur with regard to a change of resolution measured when an optimal focus position is found by changing the relative positions of the area sensor and the image-forming lens.

Description

OPTICAL INFORMATION READER AND METHOD FOR MANUFACTURING OPTICAL INFORMATION READER

The present invention relates to an optical information reader and a method of manufacturing the optical information reader.

In recent years, in response to the spread of two-dimensional codes such as QR code (registered trademark), needs of a system for optically reading two-dimensional codes attached to coupons and the like in a non-contact manner even at retail stores and convenience stores etc. Is rising.
For this reason, it is expected that the introduction of a reader capable of reading not only bar codes but also two-dimensional codes will increase from now on by using an area sensor in which imaging elements are arranged two-dimensionally. On the other hand, there is still a need to read barcodes, and even a reader capable of reading a two-dimensional code is required to read barcodes. Furthermore, there is a growing need to recognize and read passport information and the like of captured passports by using a known symbol recognition processing function (OCR).

For this reason, in an optical information reading apparatus having an area sensor, in order to image and read an information code or the like at a stable distance, an area sensor and a result for forming reflected light from the information code on this area sensor A lens barrel has been adopted as a member for adjusting and maintaining the relative position to the image lens at a predetermined focal position (best focus). In the lens barrel, a screw portion is formed on the outer peripheral surface, and in a state in which the imaging lens is assembled inside, the screw portion is screwed into the holder on which the area sensor is assembled. The relative position between the area sensor and the imaging lens has been adjusted by adjusting the screwing amount of the lens barrel. As an optical information reader which adjusts the relative position of an area sensor and an imaging lens by adjusting such screwing amount, the optical information reader disclosed by the following patent documents 1 is known, for example. There is.

Furthermore, in addition to the above-mentioned increase in needs, in public accommodation facilities, lockers, railways, and medical related fields, information codes are used for encryption, such as using an information code for encryption and for determining authenticity, and for information security measures. Cases are being introduced. In such applications, there is also a reader that improves security by using invisible light such as infrared light in addition to visible light used as conventional illumination light. Also, in general, visible light is used as illumination light, and it is used by switching to invisible light such as infrared light to prevent the illumination light from being perceived as dazzling in public places where many people can easily view the illumination light There are also many things.

Thus, as a technique related to an optical information reader using two types of illumination light, for example, a reader disclosed in Patent Document 2 below is known. This reader uses up-conversion generated by simultaneous irradiation of near-infrared light and infrared light from two different light sources, and is highly effective when it receives light reflected from a two-dimensional transparent barcode. It is possible to read a signal having an output and a high S / N ratio, and improve the information identification capability.

JP 2014-026371 JP, 2010-039958, A

In an inexpensive imaging lens employed in an optical information reading device, a portion where the image forming performance is degraded in part of the periphery of the field of view due to manufacturing variations etc. (hereinafter, also simply referred to as one-sided blurring) May occur. In an imaging lens in which such a one-sided blur does not occur, the resolving power changes according to the relative position of the area sensor and the imaging lens, and the resolving power measured when the relative position is an optimal focus position is the most It is highly appreciated.

However, in an imaging lens in which one-sided blurring occurs, in the configuration in which the relative position between the area sensor and the imaging lens is adjusted according to the screwing amount as described above, based on the resolution measured every changing the screwing amount. In order to determine the optimum focal position, one blurred portion also rotates around the optical axis. Since the resolution changes according to the position of the one blurred portion when the one blurred portion rotates as described above, the measured resolution is measured even if the relative position between the area sensor and the imaging lens is the optimum focal position. May be rated low. In such a case, there is a first problem that it is not possible to adjust to the optimal focus position.

On the other hand, in a reading apparatus in which both a light source for emitting visible light and a light source for emitting invisible light such as infrared light are mounted, an imaging field of view is usually selected due to restrictions on the arrangement of the light receiving sensor and each light source. The irradiation range of visible light and the irradiation range of invisible light with respect to (imaging field) are different. Therefore, when the visible light irradiation state is switched to the invisible light irradiation state, the irradiation range of the invisible light can not be visually recognized. Therefore, the irradiation range which has been irradiated with the visible light can be read as a readable range. There is a second problem that reading with the invisible light fails because the information code is not properly irradiated with the invisible light. The second problem may also occur in the case where the visible light and the invisible light are simultaneously irradiated to the information code and the information code is read. In particular, in the case of reading the information code located at a short distance, the positional deviation between the irradiation range of visible light and the irradiation range of invisible light becomes large, and the above problem becomes remarkable.

The present invention has been made to solve the first problem described above, and the object of the present invention is to change the relative position between the area sensor and the imaging lens to obtain an optimal focus position. It is an object of the present invention to provide a configuration capable of suppressing the influence of one blur with respect to a change in resolution to be measured (first object).

The present invention has been made to solve the second problem described above, and the object of the present invention is to mount both a light source for emitting visible light and a light source for emitting invisible light. It is an object of the present invention to provide a configuration capable of suppressing a decrease in reading performance due to a shift in irradiation range (second object).

According to a first exemplary embodiment, in order to achieve the first object,
An area sensor (23) for receiving light reflected from the information code (C) through an imaging lens (25), and optically reading the information code optically based on a signal output from the area sensor An information reader (10),
A holder (50, 150, 250, 350, 450) to which the area sensor is fixed;
A lens holding portion (60, 160, 260, 360, 460) which is assembled to the holder while holding the imaging lens and is provided with a reference plane along the optical axis (L2) of the imaging lens; Equipped
The reference surface is in surface contact with the holder when the lens holding unit is assembled such that light through the imaging lens forms an image on the area sensor, and the lens holding is performed along the optical axis. A guide surface is formed to be in sliding contact with the reference surface when the unit is moved.

According to the first aspect, the lens holding unit assembled to the holder to which the area sensor is fixed while holding the imaging lens is provided with the reference surface along the optical axis of the imaging lens. Then, when the lens holding unit is assembled to the holder so that the light through the imaging lens forms an image on the area sensor, the reference surface is in surface contact, and the lens holding unit is moved along the optical axis A guide surface is formed when the reference surface slides.

Thus, when adjusting the relative position between the area sensor and the imaging lens, the lens holding unit is moved along the optical axis with respect to the holder such that the reference surface is in sliding contact with the guide surface. That is, even when the imaging lens has one blur, measurement is performed because the one-blur portion does not rotate when the relative position between the area sensor and the imaging lens is changed to obtain the optimum focal position. The influence of one blur can be suppressed with respect to the change in resolution.

In the first aspect described above, according to an example, the area sensor has a rectangular light receiving surface, and the position where one-sided blurring occurs is grasped for each imaging lens. The lens holding unit holds the imaging lens such that the part of the field of view in which the one-sided blur occurs is positioned outside the light receiving surface on the long side of the light receiving surface. Thereby, unlike the case where the imaging lens is held so that the part of the field of view where the one-sided blurring occurs is located on the short side of the light receiving surface, the part of the field where the one-sided blurring occurs is positioned outside the imaging field of view by the area sensor Therefore, the resolution can be improved by suppressing the influence of one-sided blur.

According to another example, the reference surface is composed of a planar first reference surface and a planar second reference surface intersecting the first reference surface, and the guide surface is a sliding surface of the first reference surface. It comprises a planar first guiding surface which can be brought into contact and a planar second guiding surface which can be brought into sliding contact with the second reference surface. As described above, by configuring the reference surface and the guide surface with two flat surfaces, the configuration in which the lens holding unit is moved along the optical axis with respect to the holder can be simply realized.

According to still another example, at least a part of the flat surface on the imaging lens side of the lens holding unit functions as the first reference surface, and the holder is more than the collar unit of the lens holding unit during assembly. A portion on the imaging lens side is formed to be accommodated through the opening, and at least a part of a plane on which the opening is provided functions as a first guiding surface. Thus, not only the assembly of the lens holding portion to the holder can be easily performed, but also the first reference surface and the first guide surface can be easily brought into surface contact at the time of the assembly.

Furthermore, preferably, the flange portion is formed to cover the opening in a plane that is on the imaging lens side at the time of sliding contact. Thus, the light shielding property of the holder can be improved because the collar portion functions as a light shielding portion that prevents the light from entering through the opening.

Also, according to the second aspect,
A method of manufacturing an optical information reader for manufacturing the above-mentioned optical information reader (10), comprising:
Assembling the lens holding portion holding the imaging lens such that the reference surface is in surface contact with the guide surface with respect to the holder to which the area sensor is fixed;
Assembling an arm (510) movable along the optical axis to the lens holder;
Measuring the resolution of the area sensor sequentially while moving the arm in a direction along the optical axis such that the reference surface is in sliding contact with the guide surface;
Securing the lens holder in a state in which the arm is assembled at a peak position where the measured resolution is regarded as a peak, to the holder;
Removing the arm from the lens holder;
And the like.

In this second aspect, the lens holding portion holding the imaging lens is assembled along the optical axis after the reference surface is in surface contact with the guide surface with respect to the holder to which the area sensor is fixed. A possible arm is attached to the lens holder, and the resolution of the area sensor is sequentially measured while moving the arm in the direction along the optical axis so that the reference surface is in sliding contact with the guide surface, and the measured resolution is regarded as a peak After fixing the lens holder in a state where the arm is assembled at the position to the holder, the arm is removed from the lens holder.

As a result, when the lens holding portion is fixed to the holder at the peak position, the arm is assembled to the lens holding portion, so that the lens holding portion does not easily shift from the peak position, and the optimum determined by measuring the resolution. It is possible to reliably perform adjustment to various focal positions.

In addition, in the second aspect, for example, in the step of fixing the lens holding portion to the holder, the peak position is determined by moving the arm in the first direction along the optical axis. After moving the arm in the second direction along the optical axis so as to exceed the position, the arm is moved in the first direction toward the peak position to fix the lens holding portion to the holder at the peak position.

When switching the movement direction of the arm from the first direction to the second direction, the lens holder may not move even though the actuator is driven due to the play of the actuator for moving the arm, etc. In such a case, if the lens holder is adjusted to move in the other direction toward the peak position found while moving in the first direction, the lens may be fixed at a position deviated from the peak position. is there. Therefore, when the peak position is determined while moving in the first direction, the arm is moved in the second direction along the optical axis so as to exceed the peak position, and then the arm is moved toward the peak position. By moving the lens holder in the first direction and fixing the lens holding portion to the holder at the peak position, the occurrence of the deviation from the peak position as described above can be prevented, and the adjustment to the optimal focus position is made more reliable. Can be implemented.

For example, in the step of sequentially measuring the resolving power, the moving amount by the arm when measuring the resolving power equal to or more than a predetermined value is set smaller than the moving amount by the arm when the resolving power less than the predetermined value is measured. As a result, the measurement time for the measurement to the vicinity of the peak position is shortened, and the measurement accuracy for the measurement near the peak position is enhanced. Therefore, it is possible to achieve both the shortening of the measurement time and the improvement of the measurement accuracy.

According to the configuration according to the third aspect, in order to achieve the second object,
An area sensor (23) for receiving reflected light from an information code (C) at a rectangular light receiving surface (23a), and an optical for optically reading the information code based on a signal output from the area sensor Information reader (10),
The first light source (21) emits visible light (Lf1) as illumination light toward the imaging field of view (AR) by the area sensor, and the second light source (22) emits invisible light (Lf2).
The first light source and the second light source may be arranged in a line along a short direction of the light receiving surface.

In the third aspect, an area sensor that receives reflected light from an information code on a rectangular light receiving surface, a first light source that emits visible light as illumination light toward an imaging field of view with the area sensor, and invisible light And a second light source for emitting light, and the first light source and the second light source are arranged in a line along the short direction of the light receiving surface.

As a result, the irradiation range of visible light and the irradiation range of invisible light do not easily shift in the longitudinal direction of the imaging field with respect to the imaging field having a rectangular shape according to the shape of the light receiving surface. Normally, when reading a long information code in one direction like a bar code, the reading port is directed to the information code so that the longitudinal direction of the information code coincides with the longitudinal direction of the imaging field, that is, the longitudinal direction of the reading port become. In this state, since the irradiation range of visible light and the irradiation range of invisible light do not shift with respect to the information code in the longitudinal direction of the imaging field of view, reading occurs because both the irradiation ranges are offset in the longitudinal direction of the imaging field of view It is possible to suppress a failure, for example, a reading failure or the like which occurs because invisible light is irradiated to one longitudinal side of the information code but not to the other longitudinal side. Therefore, even when both of the first light source for emitting visible light and the second light source for emitting invisible light are mounted, it is possible to suppress the decrease in the reading performance due to the deviation of both irradiation ranges.

In addition, in the third aspect, according to the example, the first light source and the second light source are arranged such that the light receiving optical axis of the area sensor is located between the first light source and the second light source. As a result, the center of the imaging field of view, the center of the irradiation range of visible light, and the center of the irradiation range of invisible light approach in the short direction of the imaging field of view so as to coincide with each other. The size can be further reduced, and the reading performance can be improved.

In another example, the first light source and the second light source are arranged to be offset in the longitudinal direction of the light receiving surface with respect to the imaging lens. As a result, even if the first light source and the second light source are disposed close to each other in the short direction of the light receiving surface, they do not interfere with the imaging lens, so that the first light source and the second light source are brought close to each other. The size of the device can be reduced by the arrangement.

In still another example, since the first light source and the second light source are mounted on the same substrate, not only the positional deviation between the first light source and the second light source can be suppressed, but also the first light source and the second light source Can be compactly arranged, and the device can be miniaturized.

In yet another example, since the illumination lens used for the first light source and the illumination lens used for the second light source are integrally formed, not only the number of parts can be reduced for the illumination lens, but also the first light source and the second light source Can be easily arranged in a compact manner, and the device can be miniaturized.

In still another example, the first light source and the second light source are disposed such that the irradiation range of the first light source is located below the irradiation range of the second light source as viewed from the user.
Usually, when the reading port is directed to the information code displayed on a predetermined display surface, the user performs the reading operation while looking at the information code through the reading port. The upper side tends to be relatively inclined to be separated from the reading port. In this state, since the folded field of view through the predetermined display surface is on the upper side with respect to the light receiving optical axis, the first light source for emitting visible light whose light intensity is stronger than invisible light is the light receiving optical axis. If the light source is positioned on the upper side, the first light source can easily enter the folded field of view. That is, since the visible light reflected on the predetermined display surface is easily reflected, if the visible light is reflected on the captured information code, the reading performance may be degraded.

Therefore, by disposing the first light source and the second light source such that the irradiation range by the first light source is located lower than the irradiation range by the second light source when viewed from the user, the predetermined display surface is intervened. It becomes difficult for the first light source to enter the folded field of view, and it is possible to suppress the decrease in the reading performance due to the reflection of visible light with high light intensity.
In addition, the code | symbol in each said bracket shows correspondence with the specific means as described in embodiment mentioned later.

In the attached drawings:
It is a block diagram showing roughly the composition of the optical information reading device concerning a 1st embodiment. It is a figure which shows the structure of a holder in 1st Embodiment, FIG. 2 (A) shows a front view, FIG. 2 (B) shows a top view, FIG.2 (C) shows a side view. FIG. 3A is a front view, FIG. 3B is a plan view, and FIG. 3C is a side view. Show. FIG. 4A is a front view, FIG. 4B is a plan view, and FIG. 4C is a view showing a state in which the lens holding portion is assembled to the holder in the first embodiment. Fig. 3 shows a side view, partially in section, of the drawing. It is an explanatory view explaining the position of the one blur part to the image pick-up field at the time of making the imaging lens in the present invention move relative to an area sensor. It is an explanatory view explaining the position of the one blur part to the image pick-up field at the time of making the imaging lens in a prior art move relative to an area sensor. 7A is a front view, FIG. 7B is a plan view, and FIG. 7C is a side view. FIG. 8A is a front view, FIG. 8B is a plan view, and FIG. 8C is a view showing a state in which the lens holding portion is assembled to the holder in the second embodiment. , Shows a side view. FIG. 9A is a front view, FIG. 9B is a plan view, and FIG. 9C is a side view. It is a figure which shows the state which assembled | attached the lens holding part to the holder in 3rd Embodiment, FIG. 10 (A) shows a front view, FIG. 10 (B) shows a top view, FIG. 10 (C) is. , Shows a side view. 11A is a front view, FIG. 11B is a plan view, and FIG. 11C is a side view. FIG. 12 (A) shows a front view, FIG. 12 (B) shows a plan view, and FIG. 12 (C) shows a state in which the lens holding portion is assembled to the holder in the fourth embodiment. , Shows a side view. FIG. 13 (A) shows a front view, FIG. 13 (B) shows a plan view, and FIG. 13 (C) shows a side view. FIG. 14A is a front view, FIG. 14B is a plan view, and FIG. 14C is a view showing a state in which the lens holding portion is assembled to the holder in the fifth embodiment. , Shows a side view. It is a top view which shows roughly the manufacturing apparatus utilized for the manufacturing method of the optical information reader concerning 6th Embodiment. It is a side view showing roughly a manufacture device used for a manufacturing method of an optical information reader concerning a 6th embodiment. FIG. 17A is an explanatory view showing an example of a chart for measuring the contrast value, and FIG. 17B is an explanatory view showing another example of the chart for measuring the contrast value. FIG. 18A is an explanatory view showing the measurement results of the contrast value when the arm is moved in one direction, and FIG. 18B is the measurement of the contrast value when the arm is moved in the other direction. It is explanatory drawing which shows a result. It is explanatory drawing explaining the state which apply | coats a UV adhesive to the groove | channel for adhesion | attachment with respect to the lens holding part which moved to the peak position, and a holder. It is a perspective view which shows roughly the optical information reader based on 7th Embodiment of this invention. It is a right view of the optical information reader of FIG. It is a front view of the optical information reader of FIG. FIG. 21 is a block diagram schematically showing an electrical configuration of the optical information reader of FIG. 20. It is explanatory drawing explaining the positional relationship of the 1st light source and area sensor which are a direction orthogonal to the light reception optical axis in 7th Embodiment, and was seen from the 1st light source side. It is explanatory drawing explaining the positional relationship of both the light source and the area sensor which were seen from the reading opening side in 7th Embodiment. It is an explanatory view explaining an angle of an information code of a predetermined display surface at the time of reading work and an optical information reader, and Drawing 26 (A) reads an information code of a predetermined display surface in a hand-held label etc. FIG. 26B shows the case where the information code C on a predetermined display surface of a label or the like on a desk is read. FIG. 27A is an explanatory view for explaining a relationship between a folded visual field through a predetermined display surface and a light receiving optical axis, and FIG. 27A shows a state in which the first light source is positioned below the light receiving optical axis. FIG. 27B shows a state in which the first light source is located above the light receiving optical axis. FIG. 28A is an explanatory view for explaining an imaging state in which the information code is imaged in the state of FIG. 27A, and FIG. 28B shows the information code in the state of FIG. It is an explanatory view explaining an image pick-up state which picturized. It is explanatory drawing explaining the positional relationship of the 1st light source and area sensor which are a direction orthogonal to the light reception optical axis in 8th Embodiment, and was seen from the 1st light source side. It is explanatory drawing explaining the positional relationship of both the light source and the area sensor which were seen from the reading opening side in 8th Embodiment.

Hereinafter, with reference to the accompanying drawings, embodiments of various aspects in which an optical information reader having a configuration for solving the above-mentioned problems and a method for manufacturing the same will be described.
First Embodiment
An optical information reader according to a first embodiment of the present invention will be described below with reference to the drawings.
The optical information reader 10 according to the present embodiment is configured as an information code reader that optically reads an information code C such as a one-dimensional code or a two-dimensional code. Here, as the one-dimensional code, for example, a so-called bar code consisting of JAN code, EAN, UPC, ITF code, CODE 39, CODE 128, NW-7 and the like is assumed. Further, as the two-dimensional code, for example, a square information code such as a QR code, a data matrix code, a maxi code, or an Aztec code is assumed.

The optical information reader 10 is configured such that the circuit unit 20 is housed inside the case CS, and the circuit unit 20 is mainly an optical source such as the illumination light source 21, the marker light irradiation unit 22, the area sensor 23, etc. A system and a microcomputer (hereinafter referred to as a "microcomputer") system such as a memory 35 and a control unit 40 are provided.

The optical system is divided into a projection optical system and a light receiving optical system. The light projecting optical system comprises an illumination light source 21 and a marker light irradiator 22. The illumination light source 21 functions as an illumination light source capable of emitting the illumination light Lf, and includes, for example, an LED and a lens provided on the emission side of the LED.

The marker light irradiation unit 22 functions as a marker light source capable of irradiating the marker light Lm indicating the center of the imaging range by the area sensor 23. For example, the marker light irradiation unit 22 includes an LED and a lens provided on the emission side of the LED There is. Note that FIG. 1 conceptually illustrates an example in which the illumination light Lf and the marker light Lm are irradiated toward the reading target R to which the information code C is attached.

The light receiving optical system is configured of an area sensor 23, an imaging lens 25, and the like. The area sensor 23 is configured to be capable of imaging the information code C as a light receiving sensor having a rectangular light receiving surface 23a in which light receiving elements, which are solid-state imaging devices such as C-MOS and CCD, are two-dimensionally arrayed. In the present embodiment, an electric signal corresponding to the intensity of the reflected light Lr is output for each cell (pattern) of the received information code. The area sensor 23 is mounted on the sensor substrate 20 a so as to be capable of receiving incident light incident through the imaging lens 25.

The imaging lens 25 is configured to have one or more lenses, condenses incident light incident from the outside through the reading port 13, and forms an image on the light receiving surface 23 a of the area sensor 23. It functions as a possible imaging optical system. In the present embodiment, the illumination light Lf emitted from the illumination light source 21 is reflected by the information code C and the reading target R to which the information code C is attached, and the reflected light Lr is reflected by the imaging lens 25. , And forms a code image on the light receiving surface 23a of the area sensor 23.

Further, as shown in FIG. 2 to FIG. 4, the light receiving optical system is provided with a holder 50 to which the sensor substrate 20a is fixed and a lens holding portion 60 to which the imaging lens 25 is held. Note that the direction along the optical axis L of the area sensor 23 and the imaging lens 25 is the X direction, parallel to the plane where the upper surface 54 of the holder 50 and the flange lower surface 63 of the lens holder 60 make surface contact. In the following description, the direction orthogonal to Y is taken as the Y direction, and the direction orthogonal to both the X direction and the Y direction is taken as the Z direction.

The holder 50 is formed in a substantially box shape as shown in FIGS. 2A to 2C, and one end 51 of the holder 50 is opened so as to be able to fix the sensor substrate 20a. The area sensor 23 mounted on the sensor substrate 20 a is accommodated in the holder 50 by fixing the sensor substrate 20 a to the sensor substrate 20 a. The holder 50 is provided with a circular opening 52a centered on the optical axis L1 of the area sensor 23 at the other end 52 where the light receiving surface 23a of the area sensor 23 faces. The opening 52a is formed to expose only the imaging lens 25 held by the lens holding unit 60 and the vicinity thereof when viewed from the direction of the optical axis L1 in order to enhance the light shielding property of the holder 50.

Further, as shown in FIGS. 2A to 2C, the upper surface of the holder 50 has a flat upper surface 54 provided between a pair of edge portions 53 extending in the X direction along the optical axis L1 of the area sensor 23. A rectangular opening 55 is provided at the center thereof. The opening 55 is in sliding contact with the lens holding portion 60 at the time of slide adjustment, which will be described later, at

edge surfaces

56a and 56b opposed in the Y direction and along the optical axis L1 of the area sensor 23 and orthogonal to the upper surface 54. The length in the Y direction is set to restrict movement of the lens holding portion 60 in a direction different from the direction along the optical axis L1. Further, the length in the X direction of the opening 55 is set in accordance with the length that allows the lens holding unit 60 to slide at the time of slide adjustment. Further, in the pair of edge portions 53, bonding grooves 53a used for bonding and fixing after slide adjustment are respectively formed. The upper surface 54 may correspond to an example of the “guide surface” and the “first guide surface”, and the edge surfaces 56a and 56b may correspond to an example of the “guide surface” and the “second guide surface”.

As shown in FIGS. 3A to 3C, the lens holding portion 60 includes a holding portion main body 61 for holding the imaging lens 25 and a flange portion 62 connected to the upper portion of the holding portion main body 61. There is. The imaging lens 25 is held by the holding portion main body 61 in consideration of the position where one-sided blur occurs as described later. The holder main body 61 can be in sliding contact with the edge surfaces 56a and 56b of the opening 55 by having both

end surfaces

61a and 61b on the Y direction side in the vicinity of the flange 62 along the optical axis L2 of the imaging lens 25 It is formed to be orthogonal to the collar lower surface 63. The end faces 61a and 61b may correspond to an example of the "reference plane" and the "second reference plane".

The collar portion 62 is substantially flat and has a length in the Y direction set so as to be in sliding contact with the edge portion 53 during slide adjustment, and the collar lower surface 63 which is a flat surface on the imaging lens 25 side It is formed along the optical axis L2 of the image lens 25. The lower surface 63 of the flange 63 of the imaging lens 25 is aligned so that the optical axis L2 of the imaging lens 25 and the optical axis L1 of the area sensor 23 coincide with each other as the optical axis L when in sliding contact with the upper surface 54 of the holder 50. The length in the Z direction up to the optical axis L2 is set. Further, the length of the flange portion 62 in the X direction is set such that the opening 55 is covered with the lower surface 63 at all times when sliding. Further, on the upper surface of the collar portion 62, a pair of concave engaging portions 64 used at the slide adjustment and a pair of bonding grooves 65 used for adhesion and fixing after the slide adjustment are formed. The bonding groove 65 is formed to be longer in the X direction than the bonding groove 53a so as to communicate with the bonding groove 53a at any slide adjustment position. In addition, the collar lower surface 63 may correspond to an example of the “reference surface” and the “first reference surface”.

As shown in FIGS. 4A to 4C, when the lens holding portion 60 is assembled to the holder 50, the lower surface 63 and the upper surface 54 are in surface contact with each other and the end surfaces 61a and 61b and the edge surface 56a, The holding portion main body 61 which is closer to the imaging lens 25 than the collar portion 62 is accommodated in the holder 50 through the opening 55 in a state where the surface 56b is in surface contact with each other. Then, as described later, the lens holding unit 60 is moved in the X direction with respect to the holder 50 by using both engaging portions 64 so that the relative position between the area sensor 23 and the imaging lens 25 becomes an optimal focal position. After being adjusted along the slide, the lens holding portion 60 is assembled to the holder 50 in a non-slidable manner by applying a UV adhesive from the bonding groove 65 to the bonding groove 53a.

The microcomputer system includes an amplification circuit 31, an A / D conversion circuit 33, a memory 35, an address generation circuit 36, a synchronization signal generation circuit 38, a control unit 40, an operation unit 42, a liquid crystal display 43, a buzzer 44, a vibrator 45, a light emission unit 46, the communication interface 48 and the like. As its name suggests, this microcomputer system is mainly composed of the control unit 40 and the memory 35 which can function as a microcomputer (information processing apparatus), and the image signal of the information code imaged by the above-described optical system is It can be signal-processed in the form of wear and software. The control unit 40 also controls the entire system of the optical information reading device 10.

The image signal (analog signal) output from the area sensor 23 of the optical system is amplified by a predetermined amplification factor by being input to the amplifier circuit 31, and then is input to the A / D conversion circuit 33. A signal is converted to a digital signal. When the digitized image signal, that is, image data (image information) is generated and input to the memory 35, it is accumulated in a predetermined code image information storage area. The synchronization signal generation circuit 38 is configured to be able to generate synchronization signals for the area sensor 23 and the address generation circuit 36, and the address generation circuit 36 is based on the synchronization signal supplied from the synchronization signal generation circuit 38. The storage address of image data stored in the memory 35 can be generated.

The memory 35 is a semiconductor memory device, and corresponds to, for example, a RAM (DRAM, SRAM, etc.) or a ROM (EPROM, EEPROM, etc.). In the RAM of the memory 35, in addition to the above-described code image information storage area, a working area and a reading condition table used by the control unit 40 at each processing such as arithmetic operation and logical operation can be secured. There is. In addition, a reading program capable of executing reading processing for optically reading an information code, and a system program capable of controlling hardware such as the illumination light source 21 and the area sensor 23 are stored in the ROM in advance. .

The control unit 40 is a microcomputer capable of controlling the entire optical information reading apparatus 10 and comprises a CPU, a system bus, an input / output interface, etc., and can constitute an information processing apparatus together with the memory 35 and has an information processing function. . The control unit 40 functions to perform a decoding process (decoding) on a code image of an information code which is captured by the area sensor 23 and stored in the memory 35. Further, the control unit 40 is configured to be connectable to various input / output devices (peripheral devices) via the built-in input / output interface, and in the case of the present embodiment, the operation unit 42, the liquid crystal display 43, the buzzer 44, a vibrator 45, a light emitting unit 46, a communication interface 48 and the like are connected.

The operation unit 42 is configured by a plurality of keys and configured to give an operation signal to the control unit 40 in response to the user's key operation, and the control unit 40 receives the operation signal from the operation unit 42. When it is configured to perform an operation according to the operation signal. The liquid crystal display 43 is configured by a known liquid crystal display panel, and the display content is controlled by the control unit 40. The buzzer 44 is configured by a known buzzer, and is configured to generate a predetermined sound according to an operation signal from the control unit 40. The vibrator 45 is configured by a known vibrator mounted on a portable device, and is configured to generate a vibration in accordance with a drive signal from the control unit 40. The light emitting unit 46 is, for example, an LED, and is configured to light up in response to a signal from the control unit 40. The communication interface 48 is configured as an interface for performing data communication with the outside (for example, a host device), and is configured to perform communication processing in cooperation with the control unit 40.

Next, detailed configurations of the holder 50 and the lens holding unit 60 will be described.
As described above, in the imaging lens, there may be a case where one-sided blur in which the image forming performance is deteriorated occurs in a part of the periphery of the field of view due to manufacturing variations and the like. Therefore, in the conventional configuration in which the relative position between the area sensor 23 and the imaging lens 25 is adjusted according to the screwing amount of the lens barrel B holding the imaging lens 25 to the holder H, the imaging field P shown in FIG. Thus, at the time of adjustment, the one blurred portion S also rotates about the optical axis L (see the arrow in FIG. 6). Since the resolving power changes according to the position of the one blurred portion S when the one blurred portion S rotationally moves in this way, even if the relative position between the area sensor 23 and the imaging lens 25 is the optimum focal position. The measured resolution may be evaluated low.

Therefore, in the present embodiment, by employing the holder 50 and the lens holding unit 60 described above, the imaging lens 25 is slid relative to the area sensor 23 along the optical axis L to adjust the relative position. That is, the lens holding portion 60 is moved in the optical axis direction relative to the holder 50 in a state where it is in sliding contact with the upper surface 54 at the flange lower surface 63 and with the end surfaces 56a and 56b of the opening 55 at both

end surfaces

61a and 61b By being guided to slide in the X direction), the relative position between the imaging lens 25 and the area sensor 23 can be adjusted without rotating the imaging lens 25.

Then, the lens holding portion 60 is gradually slid relative to the holder 50 in a state in which the predetermined jig is engaged with both the engaging portions 64 formed in the collar portion 62, and the resolution is sequentially measured. Since the influence of one blur is suppressed with respect to the change of the resolution thus measured, the slide position (relative position) at which the resolution is evaluated to be the highest is regarded as the optimum focus position, and thus the adjusted position. A UV adhesive is applied and fixed by bonding or the like from the bonding groove 65 of the lens holding portion 60 to the bonding groove 53 a of the holder 50. Thereby, the lens holding unit 60 is assembled so as not to slide relative to the holder 50 at the optimum focal position.

In particular, in the present embodiment, as can be seen from the imaging field of view P illustrated in FIG. 5 by grasping the position where one blur occurs for each imaging lens 25, the one blur portion S is on the long side of the light receiving surface 23a. The imaging lens 25 is held by the lens holder 60 so as to be located outside the light receiving surface 23a. As a result, even when the lens holding unit 60 is slid relative to the holder 50 to measure the resolving power, it is possible to suppress imaging of the one-sided blurred portion S.

As described above, in the optical information reading apparatus 10 according to the present embodiment, the lens holding unit 60 assembled to the holder 50 while holding the imaging lens 25 is along the optical axis L1 of the imaging lens 25. A flange lower surface 63 and

end surfaces

61a and 61b are provided as reference surfaces. The lower surface 63 and the end surfaces 61a and 61b are in surface contact with the holder 50 when the lens holding unit 60 is assembled so that the light through the imaging lens 25 forms an image on the area sensor 23, and the optical axis L The upper surface 54 and the edge surfaces 56a and 56b of the opening 55 are formed as guide surfaces in sliding contact with the lower surface 63 and the end surfaces 61a and 61b when the lens holding portion 60 is moved along.

Thereby, when adjusting the relative position of the area sensor 23 and the imaging lens 25, the lower surface 63 of the flange and the end surfaces 61a and 61b are in sliding contact with the upper surface 54 and the edge surfaces 56a and 56b of the opening 55, respectively. The lens holding unit 60 is moved along the optical axis L with respect to the holder 50. That is, even if the imaging lens 25 has one blur, the one defocusing portion S does not rotate when the relative position between the area sensor 23 and the imaging lens 25 is changed to obtain the optimum focal position. The influence of one-sided blur can be suppressed with respect to the change of the resolution measured.

Furthermore, the area sensor 23 has a rectangular light receiving surface 23 a, and the position where one blur occurs is grasped for each imaging lens 25. Then, the lens holding unit 60 holds the imaging lens 25 so that the one-sided blurred portion S is positioned outside the light receiving surface 23a on the long side of the light receiving surface 23a. Thereby, unlike the case where the imaging lens is held so that the one blurred portion S is positioned on the short side of the light receiving surface, the one blurred portion S can be easily positioned outside the imaging field of view by the area sensor 23. It is possible to improve the resolution by suppressing the influence of

In addition, even if the position where the one-sided blurring occurs is not grasped for each imaging lens 25, the one-sided blurred portion S does not rotate by adopting the lens holding portion 60 and the holder 50 described above. Can be suppressed inside of the light receiving surface 23a, the influence of one-sided blur can be suppressed with respect to the change of the resolving power to be measured.

In particular, the reference surface on the lens holding portion 60 side includes a flange lower surface 63 functioning as a planar first reference surface, and

end surfaces

61a and 61b functioning as a planar second reference surface orthogonal to the first reference surface. The guiding surface on the side of the holder 50 is a planar second guiding surface capable of sliding contact with the upper surface 54 functioning as a planar first guiding surface capable of sliding contact with the first reference surface, and a second guiding surface capable of sliding contact with the second reference surface. And the edge surfaces 56a and 56b of the opening 55. As described above, by configuring the reference surface and the guide surface by two types of flat surfaces, the configuration in which the lens holding unit 60 is moved along the optical axis L with respect to the holder 50 can be simply realized.

The first reference surface and the second reference surface on the lens holding portion 60 side are provided so as to intersect at 90 ° without being orthogonal to each other, and the holder 50 with respect to the first reference surface and the second reference surface in this intersecting state. Even if the first guide surface and the second guide surface on the side are provided slidably, the structure for moving the lens holding portion 60 along the optical axis L relative to the holder 50 can be simply realized. .

Further, in the flange portion 62 of the lens holding unit 60, the flange lower surface 63 on the imaging lens 25 side functions as a first reference surface, and the holder 50 forms an image than the flange portion 62 of the lens holding unit 60 at the time of assembly. The holding portion main body 61 on the side of the lens 25 is formed to be accommodated through the opening 55, and the upper surface 54 in which the opening 55 is formed functions as a first guiding surface. Thus, not only the assembly of the lens holding portion 60 to the holder 50 can be easily performed, but also the first reference surface and the first guide surface can be easily brought into surface contact at the time of the assembly.

Further, the flange portion 62 is formed to cover the opening 55 at the flange lower surface 63 at the time of sliding contact. As a result, the collar portion 62 functions as a light shielding portion that prevents the light from entering through the opening 55, so that the light shielding property of the holder 50 can be improved.

In addition, since the lens holding portion 60 is provided with a pair of concave engaging portions 64 used when moving the holder 50 along the optical axis L, the lens holding along the optical axis L The relative movement of the unit 60 can be performed with high accuracy, and the adjustment to the optimal focus position can be reliably performed. The engagement portion 64 is not limited to being formed in a concave shape, and may be formed in a convex shape, for example, as long as it can be engaged with a jig for slide adjustment.

Second Embodiment
Next, an optical information reader according to the second embodiment will be described with reference to FIGS. 7 and 8. FIG.
The second embodiment is mainly different from the first embodiment in that a holder 150 and a lens holding portion 160 are employed instead of the holder 50 and the lens holding portion 60 described above.

Specifically, as shown in FIG. 7 and FIG. 8, the lens holding portion 160 holding the imaging lens 25 is an upper portion of the outer peripheral surface (outer surface) 161 which is circular in cross section when viewed from the surface through which the optical axis L passes. The projection 162 is formed to extend in the optical axis direction. Further, on the side of the reading opening 13 of the lens holding portion 160, a flange portion 163 used for slide adjustment is provided.

Further, the holder 150 to which the area sensor 23 is fixed has the opening 55 removed from the holder 50 described above, and an opening 152 is formed in the end portion 151 in sliding contact with the outer peripheral surface 161 of the lens holding portion 160. A concave portion 153 which is in sliding contact with at least a part of the upper surface and the side surface of the convex portion 162 of the lens holding portion 160 is formed in the upper portion of the lens holder 160.

That is, in the present embodiment, the first reference surface and the second reference surface are formed by using the outer peripheral surface 161 of the lens holding portion 160 and the convex portion 162 provided on the outer peripheral surface 161, and The two guiding surfaces are formed by utilizing the edge surface of the opening 152 provided in the holder 150 and the recess 153 provided in the opening 152.

Even with this configuration, when adjusting the relative position of the area sensor 23 and the imaging lens 25, the lens holding is performed so that the outer peripheral surface 161 and the convex portion 162 come in sliding contact with the opening 152 and the concave portion 153, respectively. The portion 160 can be moved relative to the holder 150 along the optical axis L. Therefore, when the relative position between the area sensor 23 and the imaging lens 25 is changed to obtain the optimum focal position, the one-blur portion S does not rotate, so the influence of one-blur on the change of the measured resolution is suppressed. can do.

The lens holding portion 160 is formed to be in sliding contact with the opening 152 of the holder 150 only at the lower portion of the outer peripheral surface 161, and the upper surface and the side surface of the convex portion 162 function as a first reference surface and a second reference surface. It may be configured.

Third Embodiment
Next, an optical information reader according to the third embodiment will be described with reference to FIGS. 9 and 10. FIG.
The third embodiment is mainly different from the first embodiment in that a holder 250 and a lens holding portion 260 are employed in place of the holder 50 and the lens holding portion 60 described above.

Specifically, as shown in FIGS. 9 and 10, the lens holding portion 260 holding the imaging lens 25 has an outer peripheral surface (outer surface) having a circular cross section when viewed from the surface through which the optical axis L (L2) passes. A recess 262 extending in the optical axis direction is formed on the upper portion of the H.261. Further, on the side of the reading port 13 of the lens holding portion 160, a flange portion 263 used at the time of slide adjustment is provided.

Further, the holder 250 to which the area sensor 23 is fixed has the opening 55 etc. eliminated from the holder 50 described above, and an opening 252 slidingly contacting the outer peripheral surface 261 of the lens holding portion 260 is formed at the end 251 A convex portion 253 slidably contacting at least a part of the bottom surface and the side surface of the concave portion 262 of the lens holding portion 260 is formed on the upper portion 252.

That is, in the present embodiment, the first reference surface and the second reference surface are formed by using the outer peripheral surface 261 of the lens holding portion 260 and the recess 262 provided in the outer peripheral surface 261. The guiding surface is formed by utilizing the edge surface of the opening 252 provided in the holder 250 and the convex portion 253 provided in the opening 252.

Even with this configuration, when adjusting the relative position of the area sensor 23 and the imaging lens 25, the lens holding is performed so that the outer peripheral surface 261 and the concave portion 262 come into sliding contact with the opening 252 and the convex portion 253, respectively. The portion 260 can be moved relative to the holder 250 along the optical axis L. Therefore, when the relative position between the area sensor 23 and the imaging lens 25 is changed to obtain the optimum focal position, the one-blur portion S does not rotate, so the influence of one-blur on the change of the measured resolution is suppressed. can do.

The lens holding portion 260 is formed to be in sliding contact with the opening 252 of the holder 250 only at the lower portion of the outer peripheral surface 261, and the bottom and side surfaces of the recess 262 function as a first reference surface and a second reference surface. It may be done.

Fourth Embodiment
Next, an optical information reading apparatus according to the fourth embodiment will be described with reference to FIGS. 11 and 12. FIG.
The fourth embodiment is mainly different from the first embodiment in that a holder 350 and a lens holding portion 360 are employed in place of the holder 50 and the lens holding portion 60 described above.

Specifically, as shown in FIGS. 11 and 12, the lens holding portion 360 holding the imaging lens 25 has an upper surface 361 so as to have a square cross section when viewed from the plane through which the optical axis L (L2) passes. The lower surface 362 and both side surfaces 363 and 364 are formed.

Further, the holder 350 to which the area sensor 23 is fixed eliminates the opening 55 etc. with respect to the holder 50 described above, and the end 351 is in sliding contact with the upper surface 361, the lower surface 362 and both side surfaces 363 and 364 of the lens holding portion 360. A square shaped opening 352 is formed.

That is, in the present embodiment, the first reference surface and the second reference surface are formed using the upper surface 361, the lower surface 362, and both side surfaces 363, 364 of the lens holding portion 360, and the first guide surface and the second guide surface Is formed using the edge surface of the opening 352 provided in the holder 350.

Even with this configuration, when adjusting the relative position of the area sensor 23 and the imaging lens 25, the upper surface 361, the lower surface 362, and both side surfaces 363 and 364 are in sliding contact with the opening 352. The holder 360 can be moved relative to the holder 350 along the optical axis L. Therefore, when the relative position between the area sensor 23 and the imaging lens 25 is changed to obtain the optimum focal position, the one-blur portion S does not rotate, so the influence of one-blur on the change of the measured resolution is suppressed. can do.

The upper surface 361, the lower surface 362, and both side surfaces 363 and 364 of the lens holding portion 360 are not limited to being formed in a square in cross section when viewed from the plane through which the optical axis L passes. It may be formed to have a polygonal shape in cross section including the shape having a cross section and a shape having a pentagonal cross section.

Fifth Embodiment
Next, an optical information reading apparatus according to the fifth embodiment will be described with reference to FIGS. 13 and 14.
The fifth embodiment is mainly different from the first embodiment in that a holder 450 and a lens holding portion 460 are adopted instead of the holder 50 and the lens holding portion 60 described above.

Specifically, as shown in FIG. 13 and FIG. 14, the lens holding portion 460 holding the imaging lens 25 has a circular arc shape in cross section (a cross sectional arc shape) when viewed from the plane through which the optical axis L (L2) passes. As described above, the flat surface 462 is provided on the upper side of the outer peripheral surface 461. Further, on the reading port 13 side of the lens holding portion 460, a flange portion 463 used for slide adjustment is provided.

Further, the holder 450 to which the area sensor 23 is fixed eliminates the opening 55 and the like with respect to the holder 50 described above, and the end 451 has an edge 452a and an edge with respect to the outer peripheral surface 461 and the plane 462 of the lens holding portion 460. The opening 452 is formed to be in sliding contact with the surface 452 b.

That is, in the present embodiment, the first reference surface and the second reference surface are formed using the outer peripheral surface 461 and the flat surface 462 of the lens holding portion 460, and the first guide surface and the second guide surface It forms using edge face 452a and edge face 452b of opening 452 provided.

Even with this configuration, when adjusting the relative position of the area sensor 23 and the imaging lens 25, the outer peripheral surface 461 and the flat surface 462 are in sliding contact with the

edge surfaces

452a and 452b of the opening 452, respectively. The lens holding portion 460 can be moved along the optical axis L with respect to the holder 450. Therefore, when the relative position between the area sensor 23 and the imaging lens 25 is changed to obtain the optimum focal position, the one-blur portion S does not rotate, so the influence of one-blur on the change of the measured resolution is suppressed. can do.

Sixth Embodiment
Next, a method of manufacturing an optical information reader according to the sixth embodiment will be described with reference to the drawings.
In the sixth embodiment, in the process of assembling the lens holding unit 60 and the holder 50 constituting the optical information reading device 10, the lens holding unit 60 is a holder in order to reliably carry out the adjustment operation to the optimum focal position. The second embodiment is mainly different from the first embodiment in that an arm, an X stage, and the like are used to slide gradually with respect to 50 and measure resolution sequentially and then fix them.

As shown in FIGS. 15 and 16, in the method of manufacturing the optical information reading device 10 according to the present embodiment, the mounting table 501 on which the holder 50 on which the lens holding unit 60 before bonding and fixing is assembled is mounted. And an arm 510 and an X stage 520 for moving (sliding) the lens holding unit 60 mounted on the mounting table 501 with respect to the holder 50, and a control unit 530 for driving and controlling the X stage 520. 500 will be adopted. Then, the resolving power of the area sensor 23 is sequentially measured while moving the arm 510 in the direction along the optical axis L1, and the lens holding unit 60 is fixed to the holder 50 at a peak position where the measured resolving power is regarded as a peak. Perform adjustment work to adjust the focus position.

The mounting table 501 is configured such that an image signal from the area sensor 23 of the holder 50 can be output to the control unit 530 by mounting the holder 50 at a predetermined position.

The arm 510 is provided with a pair of engagement protrusions 513 engaged with the both engagement portions 64 of the lens holding portion 60 on the lower surface of the one end side 511, and the other end side 512 is detachable with respect to the X stage 520. It is configured to be The engagement protrusion 513 is formed so as to eliminate a gap between the engaged engagement portion 64 at least in the direction (X direction) along the optical axis L1. One end side 511 of the arm 510 is formed so as to expose the two bonding grooves 65 in a state in which the two engaging protrusions 513 are respectively engaged with the corresponding engaging portions 64.

The X stage 520 is a device for moving the arm 510 assembled on the other end side 512 in the direction along the optical axis L1, and the control unit 530 controls the movement direction and the movement amount thereof. It is done.

The control unit 530 performs the focus position adjustment process to set the area sensor 23 fixed to the holder 50 and the imaging lens 25 held by the lens holding unit 60 according to the measured resolving power of the area sensor 23. It is configured to drive and control the X stage 520 so that the relative position becomes an optimal focus position. The control unit 530 may be configured as, for example, a control board including a CPU, a memory, and the like, or may be configured using an application program installed in a predetermined terminal.

Next, the manufacturing process performed when bonding and fixing the temporarily assembled lens holding portion 60 and the holder 50 so that the relative position between the area sensor 23 and the imaging lens 25 becomes an optimal focus position will be specifically described. explain.

First, the lower surface 63 and the end surfaces 61a and 61b are in surface contact with the upper surface 54 and the edge surfaces 56a and 56b, respectively, with respect to the holder 50 to which the area sensor 23 is fixed. Make a temporary assembly. Then, the holder 50 temporarily assembled in this manner is mounted at a predetermined position of the mounting table 501. As a result, the image signal from the area sensor 23 is output to the control unit 530.

Next, the arm 510 assembled to the X-stage 520 is assembled to the lens holding portion 60 so that the both engagement protrusions 513 are engaged with the engagement portion 64 respectively. Further, as shown in FIG. 15 and FIG. 16, a chart M as illustrated in FIG. 17A or 17B is disposed at a focal position within the imaging field of the area sensor 23 and desired to be adjusted.

In this state, the focus position adjustment process by the control unit 530 is started. Specifically, as illustrated in FIG. 18A, every time the X-stage 520 is driven to move the arm 510 in one direction along the optical axis according to the amount of movement set in advance, the chart M The contrast value obtained based on the output from the area sensor 23 at the time of imaging the image sensor is measured as the resolution. Here, the moving amount is a predetermined value based on a predetermined value N1 set to be lower than an expected peak value as illustrated in FIG. 18A in order to shorten the measurement time. The moving amount X2 when the contrast value of N1 or more is measured is smaller than the moving amount X1 when the contrast value less than the predetermined value N1 is measured.

Then, when the contrast value measured while moving the arm 510 in one direction starts falling below the peak and becomes equal to or less than the threshold value N2 set based on the maximum contrast value Po measured previously, the X stage The movement of the arm 510 by 520 is stopped. Then, as illustrated in FIG. 18B, the arm 510 is moved in the other direction along the optical axis L1 which is the opposite direction to the one direction, and the contrast value is sequentially measured. In the present embodiment, the moving amount X3 when moving sequentially in the other direction is set to be smaller than the moving amount X2. For example, assuming that the movement amount X3 for moving in the other direction is one step, the movement amount X2 can be five steps and the movement amount X1 can be ten steps.

Then, when the contrast value measured while moving the arm 510 in the other direction starts to fall beyond the peak, the maximum contrast value measured previously and the position of the lens holding portion 60 at which this contrast value is measured Are set as the peak value Pa and the peak position Px. Thereafter, when the contrast value measured while being moved in the other direction becomes equal to or less than the threshold value N3 set based on the peak value Pa, the movement of the arm 510 by the X stage 520 is stopped.

Then, after moving the arm 510 in one direction along the optical axis L1 so that the lens holding unit 60 exceeds the peak position Px (see arrow F1 in FIG. 18B), the arm 510 is moved again toward the peak position Px. Is moved in the other direction (see the arrow F2 in FIG. 18B), and the movement of the arm 510 by the X stage 520 is stopped at the peak position Px. Note that the other direction along the optical axis L1 may correspond to an example of “first direction”, and one direction along the optical axis L1 may correspond to an example of “second direction”.

When the lens holding portion 60 is moved to the peak position Px in this manner, a UV adhesive is applied from the bonding groove 65 to the bonding groove 53a using the UV adhesive dispenser 540 as illustrated in FIG. Do. In this state, by using a UV light or the like to fix the UV adhesive, the lens holding unit 60 is fixed to the holder 50 in a state where the arm 510 is assembled. At the time of this fixing, the arm 510 may be removed from the X stage 520.

After the lens holding unit 60 is fixed to the holder 50 in this manner, the light receiving optical system in which the lens holding unit 60 is fixed to the holder 50 at the peak position Px is obtained by removing the arm 510 from the lens holding unit 60. Complete.

As described above, in the method of manufacturing the optical information reading device 10 according to the present embodiment, the lens holding portion 60 holding the imaging lens 25 is the lower surface 63 and the end surface 61a, with respect to the holder 50 to which the area sensor 23 is fixed. After assembling so as to make surface contact with the upper surface 54 and the edge surfaces 56a and 56b, the arm 510 movable along the optical axis L1 is assembled to the lens holding portion 60, and the lower surface 63 and the end surfaces 61a and 61b are the upper surface 54. And the resolution (contrast value) measured by the area sensor 23 is sequentially measured while moving the arm 510 in the direction along the optical axis L1 so as to make sliding contact with the edge surfaces 56a and 56b, and the peak position Px at which the measured resolution is regarded as a peak And the lens holding unit 60 in a state where the arm 510 is assembled is adhesively fixed to the holder 50, and then the arm 510 is held by the lens Removed from the 60.

As a result, when the lens holding unit 60 is fixed to the holder 50 at the peak position Px, the arm 510 is assembled to the lens holding unit 60, so the lens holding unit 60 does not easily shift from the peak position Px, and the resolution is measured. By doing this, it is possible to reliably carry out the adjustment to the optimal focus position determined.

In particular, in the step of fixing the lens holding unit 60 to the holder 50, the peak position Px is obtained while moving the arm 510 in the other direction (first direction) along the optical axis L1, thereby exceeding the peak position Px. Thus, after moving the arm in one direction along the optical axis L1 (second direction: see arrow F1 in FIG. 18B), the arm 510 is directed to the peak position Px in the other direction (first direction) 18 (B) to fix the lens holding portion 60 to the holder 50 at the peak position Px.

When switching the movement direction of the arm from the first direction to the second direction, even if the X stage 520 is driven due to the play of the X stage 520 that functions as an actuator for moving the arm 510, the lens holding portion In such a case, if the lens holding unit 60 is moved in the other direction toward the peak position Px found while moving in the first direction, the peak position may be detected. It may be fixed at a position deviated from Px. Therefore, when the peak position Px is obtained while moving in the first direction, the arm 510 is moved in the second direction along the optical axis L1 so as to exceed the peak position Px, and then the peak position Px is obtained. By moving the arm 510 in the first direction and fixing the lens holding unit 60 to the holder 50 at the peak position Px, it is possible to prevent the occurrence of the deviation from the peak position Px as described above. Adjustment to the optimal focus position can be performed more reliably.

Furthermore, in the step of sequentially measuring the resolving power (contrast value), the moving amount when the resolving power of the predetermined value N1 or more is measured is measured as the moving amount X2, X3 and the resolving power less than the predetermined value N1. Make it smaller than the amount of movement X1. As a result, the measurement time for the measurement to the vicinity of the peak position Px is shortened, and the measurement accuracy for the measurement in the vicinity of the peak position Px is enhanced. Therefore, it is possible to achieve both shortening of the measurement time and improvement of the measurement accuracy.

In addition, the manufacturing method of the light reception optical system using arm 510 grade | etc., Mentioned above is applicable also to another embodiment.

The present invention is not limited to the above embodiments and modifications, and may be embodied, for example, as follows.

(1) In the

lens holding portions

160, 260, 360, and 460 in the second to fifth embodiments, in order to reliably perform adjustment to the optimum focal position, the

lens holding portions

160, 260, 360, and 460 As such, the engaging portion used at the time of slide adjustment may be formed.

(2) The present invention is not limited to being applied to an optical information reader that optically reads an information code, and optically reads character information and the like by using a well-known symbol recognition processing function (OCR). The present invention may be applied to an optical information reading apparatus, and is applied to an information reading apparatus additionally having a function other than the function of optically reading an information code or the like, for example, a wireless communication function of wirelessly communicating with a wireless communication medium. It may be done.

Seventh Embodiment
Hereinafter, an optical information reader according to a seventh embodiment of the present invention will be described with reference to the drawings.
The optical information reader 610 shown in FIGS. 20 to 23 is configured as a code reader that optically reads one or more information codes (one-dimensional code, two-dimensional code, etc.), and is a so-called gun type. A circuit portion 20 made of various electric parts and the like is accommodated inside a case 611 made of synthetic resin such as ABS resin.

The optical information reader 610, as shown in FIGS. 20 to 22, includes a main body 612 having a reading port 613 for passing illumination light and its reflected light at its end, and a reading port 613 for the main body 612. And a grip portion 615 connected to a portion different from the portion where the portion is formed and gripped by the user. As shown in FIG. 22, the reading port 613 is formed to open in a substantially rectangular shape so that the length in the left-right direction is shorter than the length in the vertical direction. An extension portion 614 is provided at the lower part of the reading port 613 in the main body portion 612, and even if the extension end portion 614a makes the extension end portion 614a contact the reading object to which the information code is attached, the information It is formed to be substantially U-shaped with its upper portion opened so that the code and marker light described later can be viewed from above. The grip portion 615 extends downward from the lower wall portion of the main body portion 12, the trigger switch 642 which can be pressed and operated is disposed near the upper end portion of the grip portion 615, and the interface near the lower end portion of the grip portion 615 Cable (not shown) is assembled.

Next, the electrical configuration of the optical information reader 10 will be described with reference to FIG. Although each element of this electrical configuration exhibits almost the same function as each component in the electrical configuration shown in FIG. 2 described above, it will be described again just in case, because different reference numerals are used.
As shown in FIG. 23, the circuit unit 620 housed in the case 611 mainly includes an optical system such as the first light source 621, the second light source 622, the area sensor 623, the imaging lens 625, the memory 635, and the control unit. And a microcomputer system (hereinafter referred to as "microcomputer").

The optical system is divided into a projection optical system and a light receiving optical system. The projection optical system is configured to include a first light source 621 and a second light source 622 as a pair of light sources. The first light source 621 is configured to include, for example, an LED 621a for emitting visible light Lf1 having a wavelength of 380 nm to 750 nm and an illumination lens provided on the emission side of the LED 621a. In addition, the second light source 622 is configured to include an LED 622a that emits invisible light Lf2 that can not be viewed like infrared light having a wavelength of 750 nm or more, and an illumination lens provided on the emission side of the LED 622a.

The light receiving optical system is configured of an area sensor 623, an imaging lens 25, and the like. The area sensor 623 is configured to be capable of imaging the information code C as a light receiving sensor having a rectangular light receiving surface 623a in which light receiving elements, which are solid-state imaging devices such as C-MOS and CCD, are two-dimensionally arrayed. In the present embodiment, an electric signal corresponding to the intensity of the reflected light Lr is output for each cell (pattern) of the received information code. The area sensor 623 is mounted on the sensor substrate 651 so as to be capable of receiving incident light incident through the imaging lens 625.

The imaging lens 625 is configured to have one or more lenses, condenses incident light incident from the outside through the reading port 613, and forms an image on the light receiving surface 623a of the area sensor 623. It functions as a possible imaging optical system. In the present embodiment, the reflected light Lr from the information code C and the predetermined display surface R to which the information code C is attached is collected by the imaging lens 625, and the code image is formed on the light receiving surface 623a of the area sensor 623. I am doing it. The detailed arrangement configuration of the optical system configured in this way will be described later.

The microcomputer system includes an amplification circuit 631, an A / D conversion circuit 633, a memory 635, an address generation circuit 636, a synchronization signal generation circuit 638, a control unit 640, a trigger switch 642, a light emission unit 643, a buzzer 644, a vibrator 645, and a communication interface 648. And so on.

The image signal (analog signal) output from the area sensor 623 of the optical system is amplified by a predetermined gain by being input to the amplifier circuit 631 and then input to the A / D conversion circuit 633 to be converted from an analog signal to a digital signal Converted to Then, the digitized image signal, that is, image data (image information) is input to a memory 635 configured by a known storage medium such as a ROM, a RAM, etc., and stored in a predetermined storage area. Synchronization signal generation circuit 638 is configured to be able to generate synchronization signals for area sensor 623 and address generation circuit 636. Address generation circuit 636 is based on the synchronization signal supplied from synchronization signal generation circuit 638. In addition, the storage address of the image data stored in the memory 635 can be generated.

The control unit 640 is a microcomputer capable of controlling the entire optical information reading device 610 and comprises a CPU, a system bus, an input / output interface, etc., and can constitute an information processing apparatus with the memory 635 and has an information processing function. . The control unit 640 functions to decode the code image of the information code captured by the area sensor 623 and stored in the memory 635. Further, the control unit 640 is configured to be connectable to various input / output devices via the built-in input / output interface, and in the case of the present embodiment, the trigger switch 642, the light emitting unit 643, the buzzer 644, the vibrator 645, A communication interface 648 or the like is connected. Thus, for example, monitoring and management of the trigger switch 642, lighting and non-lighting of the light emitting unit 643, turning on and off of the buzzer 644 capable of generating a beep sound and an alarm sound, drive control of the vibrator 45, control of the communication interface 648, etc. It is possible.

Next, the detailed arrangement configuration and the like of the optical system provided as described above will be described in detail with reference to FIG. 24 to FIG. In the following description, the lateral direction of the light receiving surface 623a is taken as the X direction, the longitudinal direction of the light receiving surface 623a as the Y direction, and a direction orthogonal to both the X direction and the Y direction (the light receiving optical axis direction) as the Z direction.

In the optical system in this embodiment, a sensor substrate 651 on which the area sensor 623 is mounted, a first illumination substrate 652 on which the LED 621 a is mounted, a second illumination substrate 653 on which the LED 622 a is mounted, etc. ing. As a result, the first light source 621 and the second light source 622, the area sensor 623, and the imaging lens 25 are disposed in the positional relationship shown in FIG. 24 and FIG.

More specifically, as shown in FIG. 25, the first light source 621 and the second light source 622 are arranged in a line along the short side direction (X direction) of the light receiving surface 623a, and The imaging lens 25 is disposed at equal intervals from the two light sources 622 so that the light receiving optical axis L of the area sensor 623 is positioned between the first light source 621 and the second light source 622. Ru. Therefore, the light receiving optical axis L, the light projecting optical axis L1 of the first light source 621 and the light projecting optical axis L2 of the second light source 622 coincide with each other in the lateral direction of the light receiving surface 623a. That is, the first light source 621 and the second light source 622 are arranged such that the distance from the LED 621a to the light receiving optical axis L is equal to the distance from the LED 622a to the light receiving optical axis L.

In the holder 650 to which the sensor substrate 651, the first illumination substrate 652, the second illumination substrate 653 and the like are fixed in the positional relationship as described above, the longitudinal direction (Y direction) of the light receiving surface 623a It is accommodated in the case 611 so as to be substantially parallel. Thus, the imaging field of view AR of the area sensor 623 having a rectangular shape in accordance with the shape of the light receiving surface 623a becomes the longitudinal direction in the left-right direction as the reading port 613, and the irradiation range of the visible light Lf1 and the irradiation of the invisible light Lf2 In the range, the center position is substantially matched in the left and right direction, and it becomes difficult to shift, and the position is shifted in the up and down direction.

Usually, when reading a long information code in one direction like a bar code, the reading port 613 is an information code so that the longitudinal direction of the information code coincides with the longitudinal direction of the imaging field of view AR, that is, the longitudinal direction of the reading port 613 It will be in the state of turning. Therefore, unlike the present embodiment, when both irradiation ranges are shifted in the longitudinal direction of the imaging field of view AR, for example, the invisible light Lf2 is irradiated on one side in the longitudinal direction of the bar code while on the other side in the longitudinal direction Reading may fail due to non-irradiation.

With respect to this problem, in the present embodiment, since the irradiation range of the visible light Lf1 and the irradiation range of the invisible light Lf2 do not shift in the longitudinal direction of the imaging field AR with respect to the information code C, both irradiation ranges are the imaging field AR It is possible to suppress the above-mentioned reading failure and the like which occur due to the deviation in the longitudinal direction of the above.

In particular, in the present embodiment, the first light source 621 and the second light source 622 are disposed such that the irradiation range of the first light source 621 is located below the irradiation range of the second light source 622 when viewed from the user. . That is, the holder 50 is accommodated in the case 11 such that the first light source 621 is positioned lower than the second light source 622.

Here, the reason for positioning the first light source 621 below the second light source 622 as described above will be described with reference to FIGS. 26 to 28.
In general, when the reading port 613 is directed to the information code C displayed on a predetermined display surface R such as a label, the user performs a reading operation while looking at the information code C via the reading port 613. For this reason, for example, when reading the information code C of a predetermined display surface R of a hand-held label etc. as shown in FIG. 26A, or a predetermined display surface of a desk top label etc. as shown in FIG. As in the case of reading the information code C of R, the predetermined display surface R tends to be inclined relative to the light receiving optical axis L so that the upper side is away from the reading port 613.

In this state, since the folded field of view AR1 through the predetermined display surface R with respect to the imaging field of view AR is on the upper side with respect to the light receiving optical axis L, as shown in FIG. When the first light source 21 for emitting the visible light Lf1 that is stronger than the light Lf2 is positioned on the upper side with respect to the light receiving optical axis L, the first light source 621 can easily enter the folded field AR1. That is, since the visible light Lf1 reflected by the predetermined display surface R is easily reflected, as shown in FIG. 28B, when the visible light Lf1 is reflected on the imaged information code C, the reading performance is May be reduced.

Therefore, in order to position the first light source 621 below the light receiving optical axis L, the irradiation range by the first light source 621 is positioned below the irradiation range by the second light source 622 when viewed from the user. The first light source 621 and the second light source 622 are disposed (see FIG. 25). As a result, as shown in FIG. 27A, it becomes difficult for the first light source 621 to enter the folded field of view AR1 through the predetermined display surface R, and as shown in FIG. The visible light Lf1 does not appear on the display, and a decrease in the reading performance caused by the reflection of the visible light Lf1 having a high light intensity can be suppressed.

As described above, in the optical information reading device 610 according to the present embodiment, the area sensor 623 that receives the reflected light from the information code C by the rectangular light receiving surface 623a, and the imaging field AR by this area sensor 623 The first light source 621 for emitting visible light Lf1 as illumination light and the second light source 622 for irradiating invisible light Lf2 toward the light source are provided. The first light source 621 and the second light source 622 have a short light receiving surface 623a. It is arranged in a line along the hand direction (X direction).

This makes it difficult for the irradiation range of the visible light Lf1 and the irradiation range of the invisible light Lf2 to shift in the longitudinal direction of the imaging field AR with respect to the imaging field AR having a rectangular shape according to the shape of the light receiving surface 623a, It is possible to suppress a reading failure that occurs because the range is shifted in the longitudinal direction of the imaging field of view AR. Therefore, even when both of the first light source 621 for emitting the visible light Lf1 and the second light source 622 for emitting the invisible light Lf2 are mounted, it is possible to suppress the decrease in the reading performance due to the deviation of both irradiation ranges.

Furthermore, the first light source 621 and the second light source 622 are arranged such that the light receiving optical axis L of the area sensor 623 is located between the first light source 621 and the second light source 622. As a result, the center of the imaging field of view AR and the center of the irradiation range of the visible light Lf1 approach the center of the irradiation range of the invisible light Lf2 in the short direction of the imaging field of view AR. Deviation from the range can be further reduced, and reading performance can be improved.

In particular, the first light source 621 and the second light source 622 are arranged such that the irradiation range of the first light source 621 is located lower than the irradiation range of the second light source 622 when viewed from the user. As a result, as described above, it becomes difficult for the first light source 21 to enter the folded field of view AR1 through the predetermined display surface R, and to suppress the decrease in the reading performance caused by the reflection of the visible light Lf1 having a high light intensity. it can.

Eighth Embodiment
Next, an optical information reader according to the eighth embodiment will be described with reference to FIGS. 29 and 30. FIG.
The eighth embodiment is mainly different from the seventh embodiment in that the first light source 621 and the second light source 622 are mounted on the same substrate.

Specifically, as shown in FIGS. 29 and 30, by mounting the LEDs 621a and the LEDs 622a on the illumination substrate 654, the first light sources 621 and the second light sources 622 are in the lateral direction of the light receiving surface 623a (X (A direction) along the longitudinal direction of the light receiving surface 623a with respect to the imaging lens 625 in the longitudinal direction (Y direction), and the distance from the LED 621a to the light receiving optical axis L and the light receiving optical axis from the LED 622a It is arranged so that the distance to L is equal. In particular, in the present embodiment, since the first light source 621 and the second light source 622 are disposed close to each other as described above, illumination in which the illumination lens of the first light source 621 and the illumination lens of the second light source 622 are integrally formed. A lens 627 is employed. In FIGS. 29 and 30, the schematic position of the illumination lens 627 is illustrated by a broken line.

As described above, the first light source 621 and the second light source 622 are disposed so as to be offset in the longitudinal direction of the light receiving surface 623a with respect to the imaging lens 625, whereby the first light source 621 and the second light source 622 are the first as compared with the seventh embodiment. Even if the light source 621 and the second light source 622 are disposed close to each other in the lateral direction of the light receiving surface 623a, they do not interfere with the imaging lens 625. Accordingly, the miniaturization of the optical information reading device 610 can be achieved along with the space saving of the holder 650 by arranging the first light source 621 and the second light source 622 to be close to each other.

Furthermore, since the first light source 621 and the second light source 622 are mounted on the same illumination substrate 654, not only the positional deviation between the first light source 621 and the second light source 622 can be suppressed, but also the first light source 621 and the second light source 622 The two light sources 622 can be easily disposed compactly, and the optical information reader 610 can be miniaturized.

In particular, since the illumination lens used for the first light source 621 and the illumination lens used for the second light source 622 are integrally formed as the illumination lens 627, not only the number of parts for the illumination lens can be reduced, It becomes easy to arrange the second light source 622 in a compact manner, and the optical information reader 610 can be miniaturized.

The configuration in which the first light source 621 and the second light source 622 are mounted on the same substrate, and the configuration in which the illumination lens used for the first light source 621 and the second light source 622 are integrally molded are also applicable to other embodiments. can do.

(1) As shown in FIG. 25 and FIG. 30, the first light source 621 is not limited to be positioned lower than the second light source 622, but, for example, a folded field of view via a predetermined display surface R The first light source 621 may be disposed above the second light source 622 in a reading work environment where the AR 1 tends to be lower than the light receiving optical axis L.

(2) When the first light source 621 and the second light source 622 are arranged in a line along the short side direction (X direction) of the light receiving surface 623a, as described above, the distance from the LED 621a to the light receiving optical axis L and the LED 622a The distance from the LED 621a to the light receiving optical axis L is not limited to be equal to the distance to the light receiving optical axis L, even if the distance from the LED 622a to the light receiving optical axis L is longer than the distance Conversely, the distance from the LED 622a to the light receiving optical axis L may be longer than the distance from the LED 621a to the light receiving optical axis L.

(3) The present invention is not limited to application to an optical information reader having a gun-type appearance, but optical information readers having various appearances, for example, optical information having a substantially box-like appearance It may be applied to a reader. Further, the present invention is not limited to application to an optical information reader for optically reading an information code, and an optical for optically reading character information and the like by utilizing a well-known symbol recognition processing function (OCR). It may be applied to an objective information reader, or it may be applied to an information reader that has other functions in addition to the function of optically reading an information code etc., for example, a wireless communication function to wirelessly communicate with a wireless communication medium. May be

DESCRIPTION OF SYMBOLS 10 ... Optical information reader 23 ... Area sensor 23a ... Light receiving surface 25 ...

Imaging lens

50, 150, 250, 350, 450 ... Holder 53 ... Edge 54 ... Upper surface (guide surface, 1st guide surface)
55 ... opening 56a, 56b ... edge surface (guide surface, second guide surface)
60, 160, 260, 360, 460 ... lens holding portion 61 ... holding portion

main body

61 a, 61 b ... end face (reference surface, second reference surface)
62 ... collar portion 63 ... lower surface of collar (reference surface, first reference surface)
DESCRIPTION OF SYMBOLS 500 ... Manufacturing apparatus 510 ... Arm 520 ... X stage 530 ... Control part L, L1, L2 ... Optical axis S ... One half blur part 610 ... Optical information reader 621 ... 1st light source 622 ... 2nd light source 623 ... Area sensor 623a ... Light receiving surface 625 ... Imaging lens AR ... Imaging field of view AR1 ... Folded field C ... Information code Lf 1 ... Visible light Lf 2 ... Invisible light R ... Predetermined display surface

Claims

An optical information reader comprising an area sensor that receives reflected light from an information code through an imaging lens, and optically reading the information code based on a signal output from the area sensor,
A holder to which the area sensor is fixed;
And a lens holding unit that is assembled to the holder while holding the imaging lens, and is provided with a reference surface along the optical axis of the imaging lens.
The reference surface is in surface contact with the holder when the lens holding unit is assembled such that light through the imaging lens forms an image on the area sensor, and the lens holding is performed along the optical axis. An optical information reader characterized in that a guide surface in sliding contact with the reference surface is formed when the unit is moved.
The area sensor has a rectangular light receiving surface,
The position where one-sided blurring that causes performance degradation in image formation occurs in a part of the field of view via the image formation lens is grasped for each of the image formation lenses,
The lens holding unit holds the imaging lens such that the part of the field of view in which the one-sided blur occurs is positioned outside the light receiving surface on the long side of the light receiving surface. Optical information reader.
The reference plane comprises a planar first reference plane and a planar second reference plane intersecting the first reference plane,
The guide surface includes a planar first guide surface capable of sliding contact with the first reference surface, and a planar second guide surface capable of sliding contact with the second reference surface. The optical information reader according to claim 1 or 2.
The lens holding portion has a collar portion,
In the flange portion, at least a part of a plane on the imaging lens side functions as the first reference surface,
The holder is formed such that a portion of the lens holding portion closer to the imaging lens than the flange portion is accommodated through the opening at the time of assembly, and at least a portion of a plane on which the opening is provided is the The optical information reader according to claim 3, wherein the optical information reader functions as a first guide surface.
5. The optical information reading device according to claim 4, wherein the flange portion is formed to cover the opening on a plane that is on the imaging lens side at the time of the sliding contact.
The first reference surface and the second reference surface are formed by using a convex portion provided on an outer surface of the lens holding portion.
The optical information reader according to claim 3, wherein the first guide surface and the second guide surface are formed by using a recess provided in the holder.
The first reference surface and the second reference surface are formed by using a recess provided on the outer surface of the lens holding unit.
The optical information reader according to claim 3, wherein the first guide surface and the second guide surface are formed using a convex portion provided on the holder.
The lens holding portion is characterized in that at least a part of an outer peripheral surface having a polygonal shape in cross section when viewed from a surface through which the optical axis passes functions as the first reference surface and the second reference surface. The optical information reader according to claim 3.
The said lens holding | maintenance part is formed so that at least one part of the outer peripheral surface which becomes a cross-sectional circular arc shape seeing from the surface through which the said optical axis passes may function as the said reference surface. Optical information reader.
The said lens holding | maintenance part is provided with the engaging part utilized when moving it so that the said holder may be followed along the said optical axis, The said claim | item 1-9 characterized by the above-mentioned. Optical information reader.
A method of manufacturing an optical information reading device for manufacturing an optical information reading device according to any one of claims 1 to 10, comprising:
Assembling the lens holding portion holding the imaging lens such that the reference surface is in surface contact with the guide surface with respect to the holder to which the area sensor is fixed;
Assembling an arm movable along the optical axis to the lens holder;
Measuring the resolution of the area sensor sequentially while moving the arm in a direction along the optical axis such that the reference surface is in sliding contact with the guide surface;
Securing the lens holder in a state in which the arm is assembled at a peak position where the measured resolution is regarded as a peak, to the holder;
Removing the arm from the lens holder;
A method of manufacturing an optical information reader, comprising:
In the step of fixing the lens holding portion to the holder, the peak position is obtained while moving the arm in a first direction along the optical axis, so that the light of the arm is moved beyond the peak position. After moving along the axis in a second direction opposite to the first direction, the arm is again moved in the first direction toward the peak position, and at the peak position, the arm is moved. The method for manufacturing an optical information reader according to claim 11, wherein a lens holding portion is fixed to the holder.
In the step of sequentially measuring the resolving power, the moving amount by the arm when the resolving power of a predetermined value or more is measured is smaller than the moving amount by the arm when the resolving power less than the predetermined value is measured. A method of manufacturing an optical information reader according to claim 11 or 12, characterized in that:
An optical information reader comprising: an area sensor that receives light reflected from an information code by a rectangular light receiving surface, and optically reading the information code based on a signal output from the area sensor,
A first light source that emits visible light as illumination light toward a field of view captured by the area sensor; and a second light source that emits invisible light.
The optical information reader according to claim 1, wherein the first light source and the second light source are arranged in a line along a short direction of the light receiving surface.
15. The apparatus according to claim 14, wherein the first light source and the second light source are disposed such that the light receiving optical axis of the area sensor is positioned between the first light source and the second light source. Optical information reader.
And an imaging lens configured to condense reflected light from the information code and form an image on the light receiving surface.
The optical information reader according to claim 14, wherein the first light source and the second light source are arranged to be displaced in the longitudinal direction of the light receiving surface with respect to the imaging lens.
The optical information reader according to any one of claims 14 to 16, wherein the first light source and the second light source are mounted on the same substrate.
The optical information reader according to any one of claims 14 to 17, wherein an illumination lens used for the first light source and an illumination lens used for the second light source are integrally formed. .
The first light source and the second light source are disposed such that the irradiation range by the first light source is located lower than the irradiation range by the second light source when viewed from the user. The optical information reader according to any one of 14 to 18.