JPS6022610A - Line sensor camera for measuring size - Google Patents

Abstract

PURPOSE:To expand the measuring range of a line sensor camera for measuring size and to make the precision measurement of a large object easy by using a prism pair movable in the optical axis direction and changing the imaging conditions of the measuring object on the line sensor. CONSTITUTION:If a measuring object is 1, the parallel rays irradiated through the peripheral part (diameter =D1) thereof are bent at right angles by the Q1 on the side of a prism 9 placed in the position 12 (with respect to the ray of the right half in the figure) and thereafter the rays are bent respectively at right angles by the 1st prism 5 and the 2nd prism 7, by which the rays are made again parallel with the optical axis. Such rays are converted by a lens 2 to form the image at one point P on a line sensor 3. If the prism 9 is similarly placed in the position (c), the parallel rays passing the object 1' (diameter =D2) pass the point Q2 on the prism and form the image likewise at the point P'. The size of the large object can be consequently measured by moving upward the prism 9. On the other hand, the measurement of an object having the lower limit in size is accomplished simply by moving the position of the prism 9 to the position (a) so as to pass the one point Q3 on the optical axis.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a line sensor camera for dimension measurement, and aims to expand its measurement range.

Conventional line sensor cameras have a problem in that the measurement range is narrow because the size of the line sensor is limited.

Therefore, a method has been considered to widen the measurement range by dividing the measurement range into a fixed length portion and a variable length portion as shown in FIG. In the same figure, 1 is the measuring object (diameter - D
), 2 is a lens for fully converging parallel light beams and forming an image on the line sensor element 3; 4 and 5 are a first pair of prisms having a movable structure for bending the parallel light beams completely passing around the measuring object 10 at right angles; 6; Reference numeral 7 designates a second pair of prisms 4'fI) which is fixed in order to bend the first prisms 4 and 5f at right angles to change the beam into a beam parallel to the axis.

In the line sensor camera configured in this way, the measurement part is a fixed part W and a variable 1'% part. Divided into L2, the dimensions of the object 1 are expressed as these cells 11+, so the distance between the first prisms j4 and 5 is widened to J+"2.
If you increase the value of , you will be able to measure the dimensions of larger objects. However, in order to measure objects of small dimensions according to the double method, the distance between the first pair of prisms 4, 6 must be shortened, while the second pair of prisms 6, 7 There was a drawback that there were areas that could not be measured every time.

The present invention eliminates the above drawbacks by devising the moving direction of the prism pair. This will be explained below along with examples.

FIG. 2 shows an embodiment of the present invention.

In the figure, 1 to 7 correspond to the same reference numerals in FIG. However, the positions of the prisms 4 and 5 are fixed, unlike those in FIG. Reference numerals 8 and 9 indicate a third pair of prisms movable in the direction of the optical axis xx', and a fourth pair of prisms fixed at 10°11rr. The third pair of prisms 8 and 9 are structured so that they can be moved from A, which is the farthest from the object to be measured, to the base, and so on.

Next, the operation will be explained based on this configuration.

First, if the measurement object is 1, its periphery (diameter - D +
) 'e The parallel ray irradiated through is (below, to simplify the explanation, the right half of the ray in Figure 2 will be explained) 12
The prism 9 placed at the position is bent at a right angle by the athlete's Ql, and then bent at right angles by the fourth prism 11, the first prism 5, and the second prism R. As a result, it is parallel to the optical axis again. The light is then converged by the lens 2 to form a single point PK image on the line sensor 3. Similarly, if prism 9 is placed at position C, measurement object 1' (diameter - D2)'
The parallel light beam passing through ffi passes through point Q2 on the prism and forms an image at point P'. As a result, by moving the entire prism 9 in the direction, the size of the large object is
tl can be determined. On the other hand, when the size of the object is small, the limit is to pass through one point Q on the optical axis; the position of the sea urchin prism 9 may be moved to the position A.

This corresponds to the case where the dimensions of the object are zero. Therefore, according to the above-mentioned embodiment, by moving the position of the prism 9 in the following order, the measurement object can be used continuously over a wide range of dimensions from O to Fil. The actual dimensions of the object are given by:

D==2a+M@Pi・QThe magnification coefficient of the M lens,
Pi is the pitch of the licensor element, and Q is the read count number. However, in -, we set the length of D to be boxed out in the second term on the right-hand side of the above equation in advance using the reference position of the prism, and then calculate the amount of movement of the prism from the reference position (=a). In this case, D is determined from these by a one-circuit arithmetic means.

Although +d and the prism pair 8 and 9 are made movable in the above embodiment, the same effect can also be achieved by making the prism pair 6+7 movable in the optical axis direction. Furthermore, since the role of each prism is to bend the light beam at right angles, a mirror surface may be used instead of the prism to reflect the light beam.

A micrometer may be used as a means for measuring the amount of movement of the prism pair 8, 9, or a movement amount encoder may be used to automate the display method.

FIG. 3 is an embodiment showing the configuration of the dimension reading section of the present invention. In the figure, 23 (is an operation unit for controlling the micrometer, 22 is a movement encoder for electrically reading out the movement of the micrometer, and 21 is a reading of the encoder and a count number of the licensor 3). A calculator 24 calculates the dimensions of the object to be measured 1 from the measured object 1, and 24 is a display unit that displays the calculation results.

As explained above, according to the present invention, the fixed range of the line sensor camera for dimension measurement can be expanded by changing the imaging conditions of the measurement object on the licensor beam using a pair of prisms movable in the optical axis direction. As a result, it has a practical effect that allows precise measurement of large objects to be easily performed.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of the conventional dimension measurement line sensor 3 upper layer, FIG. 2 is a configuration diagram of the dimension measurement line sensor 3 upper layer in an embodiment of the present invention, and FIG. 3 is a line sensor according to the present invention. Camera dimensions reading? It is a block diagram of Xls. 1.Measurement object, 4, 5, 10.11 ・Prism, 8
, 9-... First prism, 6, 7-... Second prism, 2... Lens, 3... Line sensor element. Name of representative Patent attorney Toshio Nakao and 1 other person 1st
Figure 2

Claims (1)

[Claims] A first prism is provided on the other side of the object to be measured to which a light beam from one direction is applied, and forms a pair that bends the parallel light beam in a direction perpendicular to the optical axis; and a first prism is provided on the line sensor element.
a second prism forming a pair on the optical axis of the lens; and the first prism.
means for directing the light beam from the first prism to the second prism; A line sensor camera for measuring dimensions, characterized in that one of the second prisms is movable in the optical axis direction.