As may be known, in manufacturing and/or otherwise producing printed circuit boards (PCBs) and printed circuit board assemblies (PCBAs) (i.e., ‘boards’, ‘circuit boards’, and the like), an important part of the manufacturing process is inspecting each board during and/or after manufacturing to ensure that the elements on each board are the correct parts and/or are properly placed, secured, and/or otherwise mounted to the board, and/or also to ensure that the board itself is proper. For example, it may be that each diode on the board should be inspected to ensure that the diode is not backward, and that a solder joint on the board that is particularly prone to error should be inspected to ensure such error has been avoided, among many other things.
In at least some instances, inspecting each board has been done manually by a human inspector who maneuvers to visually inspect the aspects of the board which require inspection, perhaps by picking up the board and moving same around to optimize such visual inspection while possibly using a visual aid such as a ring lamp, microscope, eyepiece, or other magnification device. As should be appreciated, though, picking up and moving the board for such visual inspection is to be discouraged for many reasons: touching the board improperly could impart a static shock that could damage the board; parts on the board may not necessarily be secured thereto when picked up and could be displaced from the board thereby; picking up the board disturbs the board from any previous alignment of the board that was achieved with regard to manufacturing machinery; picking up the board does not necessarily ensure an optimal view of a particular object on the board is achieved; and the like.
Picking up the board may be avoided, although performing a manual inspection of the board in such an instance may also be discouraged. For one thing, a human inspector may be hindered from visually inspecting the board in situ by the presence of the manufacturing machinery. For another thing, visually inspecting the board in situ may unreasonably require the human inspector to move about the board in an awkward manner in order to achieve a necessary view, or may unreasonably require the human inspector to assume an awkward position in order to achieve the necessary view. Moreover, regardless of whether the board is picked up, a human inspector may not be able to properly inspect an aspect of the board if, for example, lighting is inadequate, the aspect to be inspected is relatively small, the aspect is obstructed by another object on the board, and the like.
Accordingly, it is known that inspecting each board may be performed by or with the aid of an optical inspection system. Generally, with such an optical inspection system, one or more cameras or other imaging devices are maneuvered about the board in a controlled manner, and/or vice versa, so that aspects of the board to be inspected are captured and/or viewed as images. Each such image may then be compared to a reference image or numerically analyzed to determine whether the aspect is correct, either by a human inspector or by an automated computer process, or can be displayed on a monitor for viewing by the human inspector, for example.
Note, though, that prior optical inspection systems are either awkward or otherwise unsatisfactory. For example, some prior systems require multiple cameras, each of which is differently fixed with regard to the view obtained therefrom. Other prior systems also have cameras that are adjustable with regard to the view obtained therefrom, but in manners that are limited.
Accordingly, a need exists for an optical inspection system for printed circuit boards (PCBs) and printed circuit board assemblies (PCBAs) where the system includes a camera or other optical imaging device which is highly adjustable in an automated manner with regard to the view available therefrom. Specifically, a need exists for such a system with an imaging device whose view can be adjusted with regard to an X, Y position on a surface of a board under inspection, a Z height of the view on, above, or below the surface of the board, an angle of incidence with respect to the surface of the board, and an angle of approach with regard to the surface of the board. The view can then be displayed and/or captured so that a human operator or a computer algorithm can analyze images of the board as part of a manual, automatic, or semi-automatic inspection process.