JP2003114199A - Printed-state inspection device for optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printed-state inspection device for optical disk that is reduced in size and manufacturing cost. SOLUTION: This printed-state inspection device is provided with a camera 1 which is arranged to face the printed surface 101a of an optical disk 101 so that its optical axis X may become coincident with that of the disk 101, a half mirror 2 arranged between the camera 1 and disk 101 so that its reflecting surface 2a may be placed at the angle of 45 deg. to the optical axis X of the camera 1, and a lens 5 which is arranged between the mirror 2 and disk 101 so that its optical axis may become coincident with that X of the camera 1 and causes the light reflected by the printed surface 101a of the disk 101 to form an image at the position of the camera 1. This inspection device is also provided with an illumination unit 6 which is arranged on a straight line L passing the intersection between the reflecting surface 2a of the mirror 2 and optical axis X of the camera 1 and, at the same time, crossing the optical axis X at right angles and has many LEDs 7 provided in a plane crossing the straight line L at right angles and an LED controller which selectively drives the LEDs 7 by dividing the LEDs 7 into those arranged inside an area having a prescribed diameter provided around the straight line L and those arranged outside the area.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an apparatus for inspecting a printing state of an optical disk having one side printed. 2. Description of the Related Art Generally, on one surface of an optical disk such as a compact disk, recorded contents, a name of a manufacturer, a design, and the like are printed. In this printing, defects such as pinholes, blurring and bleeding, adhesion of dust, color unevenness, etc. may occur due to dust or bubbles mixed into the ink at the time of printing,
It is necessary to inspect for these defects before shipping. FIG. 3 is a schematic diagram showing an example of a conventional apparatus for inspecting such a defect. This device is a camera 1
, A half mirror 2, a halogen lighting unit 3, and a fluorescent lighting unit 4. The camera 1 is a CCD camera, which is mounted on a frame (not shown) so as to face the printing surface 101a of the optical disk 101 and to have the optical axis X coaxial with the optical disk 101. The half mirror 2 is mounted on a frame between the camera 1 and the optical disk 101 such that the reflection surface 2a forms an angle of 45 ° with the optical axis X. The halogen lighting unit 3 is disposed on a straight line L passing through the intersection of the reflection surface 2a of the half mirror 2 and the optical axis X and orthogonal to the optical axis X. The optical disk 101 is controlled by the halogen lighting unit 3 and the half mirror 2.
, So-called co-axial illumination is performed. That is, light substantially parallel to the optical axis X is applied to the printing surface 101 of the optical disc 101.
a. The fluorescent lighting unit 4 is formed in a ring shape and is arranged so as to be coaxial with the optical axis X. The fluorescent lighting unit 4 irradiates the entire printed surface 101a of the optical disc 101 with diffused light. [0008] With this device, a pinhole on the printing surface 101a,
When inspecting for blurring, bleeding, adhesion of dust, and the like, the halogen lighting unit 3 is turned on, and the white light is reflected by the reflecting surface 2a of the half mirror 2 and is irradiated on the printing surface 101a of the optical disk 101. This light is printed on the printing surface 101a.
And is incident on the camera 1. As described above, by reflecting the light emitting portion of the halogen lighting unit 3 on the printing surface 101a, flaws, dust, and the like on the printing blank portion (mirror surface) emerge and become easy to detect. The image captured by the camera 1 is processed by an image processing device (not shown), and the presence or absence of a defect is determined. On the other hand, when inspecting color unevenness, the fluorescent illumination unit 4 is turned on, a part of the emitted diffused light is irradiated on the printing surface 101a of the optical disk 101, and a part of the reflected light is emitted from the camera 1 Incident on. An image captured by the camera 1 is processed by an image processing device (not shown), and the presence or absence of a defect is determined. [0011] In the above-mentioned conventional inspection apparatus, since two illumination units are provided, there are problems that the apparatus becomes expensive and it is difficult to reduce the size. [0012] In order to solve the above-mentioned problems, the present invention is for inspecting the printing state of an optical disk having one surface printed thereon, and comprises the steps of: A camera facing the surface and arranged so that the optical axis is coaxial with the optical disc; and a half mirror arranged between the camera and the optical disc such that a reflection surface forms an angle of 45 ° with the optical axis. And a lens arranged between the half mirror and the optical disc so as to be coaxial with the optical axis, and a lens that forms an image of light reflected by the printing surface at a position of the camera; and a lens of the reflection surface and the optical axis. An illumination unit having a plurality of LEDs disposed on a straight line passing through an intersection and orthogonal to the optical axis and provided in a plane orthogonal to the straight line;
An LED controller for selectively driving an LED within a region of a predetermined diameter centered on the straight line and an LED outside the region, and when the LEDs in the region are turned on, the entire printing surface is A light beam substantially parallel to the optical axis, and when the LED outside the area is turned on, the entire printed surface is irradiated with diffused light. Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a printing state inspection apparatus according to an embodiment of the present invention, and FIG.
FIG. 3 is a sectional view taken along line AA of FIG. In the present embodiment,
The same parts as those of the above-described conventional inspection apparatus are denoted by the same reference numerals, and redundant description is omitted. In this inspection apparatus, a plano-convex lens 5 is mounted on a frame between the half mirror 2 and the optical disk 101 so as to be coaxial with the optical axis X, and the diameter thereof is larger than the diameter of the optical disk 101. ing. Further, the camera 1 is disposed at the position of the focal length of the lens 5. Furthermore, in this inspection apparatus, one illumination unit 6 is positioned on a straight line L passing through the intersection of the reflection surface 2a of the half mirror 2 and the optical axis X and orthogonal to the optical axis X. No illumination unit is provided between the half mirror 2 and the optical disk 101. As shown in FIG. 2, the lighting unit 6 has a large number of LEDs 7 provided in a circular plane P centered on the straight line L and perpendicular to the straight line L. They are regularly arranged so as to be uniformly distributed over the entire surface of the plane P. These LEDs 7 are controlled by an LED controller (not shown). This controller is a microcomputer (not shown) that controls the entire apparatus.
Are stored in the ROM. Based on information input via an operation panel (not shown), the controller includes all the LEDs 7 located in a circular area R centered on the straight line L and smaller in diameter than the plane P, and One of all the LEDs 7 located outside R is selectively driven. The diameter of the region R is equal to the diameter of all L in the region R.
When the light emitted from the ED 7 is reflected by the half mirror 2 and passes through the lens 5, the light is substantially parallel to the optical axis X and is
The light flux is set to be approximately the same diameter as 1a. Next, the operation of the inspection apparatus will be described. When inspecting pinholes, blurring and bleeding, adhesion of dust, etc. on the printing surface 101a, based on the input information,
All the LEDs 7 in the region R are turned on, and the white light is reflected by the reflection surface 2a of the half mirror 2 and is incident on the lens 5 to form a light flux substantially parallel to the optical axis X and the optical disk 101
Is irradiated on the entire printing surface 101a. This light is reflected in a direction perpendicular to the printing surface 101a, enters the lens 5, passes through the half mirror 2, forms an image at the position of the camera 1, and is picked up by the camera 1. The image captured by the camera 1 is processed by an image processing device (not shown), and the presence or absence of a defect is determined. On the other hand, when the color unevenness of the printing surface 101a is inspected, all the LEDs 7 outside the region R are turned on based on the input information, and the white light is reflected by the reflecting surface 2a of the half mirror 2. Is reflected by the optical disk 1 as diffused light.
01 is applied to the entire printing surface 101a. A part of this light is reflected in a direction orthogonal to the printing surface 101a, enters the lens 5, passes through the half mirror 2, forms an image at the position of the camera 1, and is picked up by the camera 1. Then, the image is processed by an image processing device (not shown).
And the presence or absence of a defect is determined. As described above, one illumination unit 6 is divided into a coaxial incident illumination for detecting pinholes, blurs and blurs, and adhesion of dust on the printing surface 101a, and a diffused illumination for detecting uneven color. Since the number of lighting units can be reduced by selectively switching to any one of the above, the size of the device can be reduced and the manufacturing cost can be reduced. In the above-described embodiment, an LED that emits white light is used as the LED. However, an LED that emits another color may be used as long as it can detect a flaw or dust. In addition, various modifications can be made to the above-described embodiment without departing from the gist of the present invention. As described above, according to the present invention,
Selectively switching one lighting unit between coaxial epi-illumination for detecting pinholes, blurring and bleeding, and adhesion of dust on the printing surface, and diffused illumination for detecting color unevenness Since the number of lighting units is reduced, the size of the apparatus can be reduced, and the manufacturing cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of an optical disk print state inspection apparatus according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line AA of FIG. FIG. 3 is a schematic configuration diagram of a conventional optical disk print state inspection apparatus. [Description of Signs] 1 Camera 2 Half mirror 5 Lens 6 Lighting unit 7 LED

   ────────────────────────────────────────────────── ─── Continuation of front page    F term (reference) 2G051 AA71 AB11 BA01 BA20 BB01                       BB11 CA04 CA06 CC11                 5D121 AA03 HH14 HH18 JJ05

Claims (1)

Claims 1. An apparatus for inspecting a printing state of an optical disk having one surface printed thereon, the optical surface being opposed to a printing surface of the optical disk and having an optical axis coaxial with the optical disk. A half mirror disposed between the camera and the optical disc such that a reflection surface forms an angle of 45 ° with the optical axis; and the optical axis between the half mirror and the optical disc. A lens that is arranged coaxially with the lens and forms an image of the light reflected by the printing surface at the position of the camera; and a lens that passes through the intersection of the reflection surface and the optical axis and is orthogonal to the optical axis. A lighting unit having a large number of LEDs provided in a plane orthogonal to the straight line; and connecting the large number of LEDs to an LED within a region of a predetermined diameter centered on the straight line. An LED controller that selectively drives the LEDs outside the area, and when the LEDs inside the area are turned on, light substantially parallel to the optical axis is applied to the entire printing surface, and L outside the area is used.
An apparatus for inspecting the printing state of an optical disk, wherein when the ED is turned on, diffused light is applied to the entire printing surface.