JPS63115154A - Microfilm reader - Google Patents

Abstract

PURPOSE:To speed up retrieval by detecting the peripheral sides of an image projected on a microfilm and finding the tilt quantity of the image, and correcting the inclination of an image projected on a screen. CONSTITUTION:When the frame number of a desired image is inputted, a roll film is fed forward or backward while blip marks S1, S2, S3, etc., are detected by an image retrieval sensor 20, and the desired frame is moved to a projection position. When the desired frame A1 or A3 passes by peripheral side sensors alphaand beta or alpha' and beta', those sensors detect the image peripheral sides and computes the tilt angle of the image from the detection time difference. This computation result is inputted to a pulse motor and a lens with a prism is rotated to rotate the image on the screen and correct its inclination automatically, thereby speeding up the retrieval.

Description

[Detailed Description of the Invention] The present invention searches for a desired image from among a large number of images imprinted on a microfilm such as a roll film or a fish film while driving the microfilm. , relates to a microfilm reader that projects onto a screen.

It is desirable for images to be imprinted on microfilm such as roll film to be imprinted at the correct angle, but especially for small items such as stock certificates and checks, it is difficult to imprint images taken with a data entry camera. The current situation is that each image has a different slope due to the If such an image is retrieved using a microfilm reader and projected directly onto the screen, the image will be tilted on the screen, which is very unsightly, so the operator must move the film carrier or prism-equipped lens to correct the tilt of the image. ing.

However, it is troublesome for the operator to manually modify each image one by one, and there is a problem in that it is difficult to speed up the search.

SUMMARY OF THE INVENTION Therefore, the present invention provides an extremely useful microfilm reader that automatically corrects to a normal angle when projecting an image onto a screen even if the image recorded on the microfilm is tilted, thereby enabling high-speed retrieval. The purpose is to

In order to achieve the above-mentioned object of solving the voice problem, the microfilm reader according to the present invention performs image retrieval to detect when a desired image among a large number of images imprinted on a microfilm has reached the projection position. a side sensor that detects at least two points on the sides of the image imprinted on the microfilm; and a side sensor that detects at least two points on the sides of the image imprinted on the microfilm; and image correction means that corrects the image tilt angle by rotating the image projected on the screen in the opposite direction by the amount of tilt determined by the calculation. There is.

The operation of the present invention will be explained in detail in Examples.

Figure 6 shows an overall external view of a microfilm reader to which the present invention is applied, in which 1 is a screen, 2 is an insertion port for inserting a cassette containing a roll film as an example of a microfilm, and 3 is an insertion port for inserting a cassette containing a roll film as an example of a microfilm. The roll film carrier section 4 is a control section operated by an operator to search for a desired image from among a large number of images imprinted on the roll film.

FIG. 2 shows an outline of the internal configuration of the microfilm reader. In the figure, reference numeral 5 denotes a cartridge that accommodates the roll film 6. When the cartridge is inserted into the roll film carrier section 3 through the insertion port 2 in Figure 6, an internal switch (not shown) is turned on and the film transport drive mechanism (not shown) is activated. The leading edge of the roll film 6 passes through the first guide 7 and reaches the feed roller 8a.
, 8b. Then, due to the conveying force of the feed rollers 8a and 8b, the tip of the roll film is further moved to the second guide 9.
→ Encoder roller 10a, auxiliary roller IQb → Third guide 1) - Pressure plate part 12 at the projection position onto the screen 1
- Fourth guide 13 -> Guide roller 14 to be supplied to winding wheel 15.

A film transport drive mechanism (not shown) is also connected to this take-up reel 15 so that the roll film 6 can be transported in both forward and reverse directions together with the transport drive mechanism on the cartridge side. The pressure plate section 12 consists of a fixed-side upper plate 12a in which an aperture having approximately the same size as the image on the film is formed in the center, and a lower transparent plate 12b facing the plate.

A light source 16, a reflecting mirror 17, and a condenser lens group 18 for creating parallel light are provided below the lower transparent plate 12b, and convert the light emitted from the light source 16 into parallel light between the pressure plate parts 12a and 12b. ttut to the roll film portion 6a sandwiched between. The light transmitted through the film 6a passes through a known optical system 19 consisting of a prism-equipped lens 18, a reflecting mirror, and a lens, is magnified at an appropriate magnification, and is projected onto the screen 1.

The upper plate 12a has an image retrieval sensor (see FIG. 3) that detects flip marks (not shown) formed corresponding to each image on the roll film and detects when a desired image has reached the projection position. ) is provided.

The prep mark detection operation of this sensor and the transport drive mechanism of the roll film 6 are connected through the controller 4. When an operator inputs the number of frames into the controller to search for a desired frame image, the image search sensor 20 While sensing the flip marks, the roll film 6 is moved forward or backward by the film transport drive mechanism to move the desired frame to the projection position.

On the back side of the screen 1, as shown in FIG. 3, there is a side sensor α for detecting two points on the side of the image.

β, α゛, β'' are arranged two each at the front and rear in the film transport direction. Side sensors α, β, α°.

As for β', it is sufficient as long as it can distinguish between a transparent area where no image is imprinted on the film and an opaque image area, and for example, an optical sensor such as a photodiode can be used. Two side sensors α.

The arrangement direction of β, (α゛, β°) is a direction perpendicular to the film conveyance direction, in other words, a direction perpendicular to the image side when the image is projected at a normal angle. Further, the distance l between the two side sensors α and β, and between α′ and β′ is smaller than the length H of the side m of the image (indicated by AI and A2 in the figure) (l<H). The reason why the interval E between the two sensors is set to l<H is to enable detection of two points on the sides of the image even if the image is tilted. Furthermore, the reason why two side sensors are provided on both sides of the film transport direction is to enable image tilt correction both when the film moves forward and when the film moves backward. That is, the side sensors α and β on one side of the screen 1 detect the image side when the film is moving forward (p direction), and the side sensors α'' and β'' on the other side of the screen detect the image side when the film is moving backwards (q direction). In addition, all side sensors α, β, α°, and β′ are set to a disabled state in which they do not sense until the image of the desired frame reaches near the projection position.For example, , when searching for the 150th frame image, when the film is moving forward, the side sensors α and β are disabled until the 149th frame image passes the projection position.Similarly, when the film is moving backwards, the side sensors α and β are disabled. Sometimes, the side sensors α° and β° are disabled until the 151st frame image passes through the projection position.In the figure, SL, S2, . . . are flip marks.

FIG. 4 shows the two side sensors α and β (α゛).

β°) shows the operation of detecting the image side.

When the image A1 travels in the p direction in a tilted state as shown in the figure, the side sensor β first detects the image side m, and then, after a certain time delay, the side sensor α detects the image side m. do.

In this case, the conveyance amount of the film is the encoder roller 0a
Since it is known, the length T in FIG. 4(a) can be found from the time difference between when the two sensors α and β detect the side m of the image. So, what is the distance between the two sensors α and β? Therefore, the tilt angle θ of the image can be found by calculating θ=j a n−′ −. Similarly, when the film is moving backwards, the image inclination θ' is determined from the time difference between when the two side sensors α° and β° detect the image side m' (see Figure (b)). Note that one of the two side sensors, for example, side sensor β (β゛), is used as a reference sensor, and the other side sensor α (α°) is set based on the time when this reference sensor detects the image side. Depending on when the sides of the image are detected, it is also possible to detect which direction the image is tilted.

The calculation of the image tilt as described above is performed by the CPU shown in Figure 1.
The calculation is performed by the calculation means 21 consisting of: The calculation result is then input to a pulse motor, which will be described later, to control the image projected on the screen to be rotated in the opposite direction by the same angle as its inclination angle (θ).

The prism-equipped lens 18 rotates the image projected on the screen by rotating it, and focuses the image by moving along the optical path, and its detailed configuration is shown in FIG. That is, as shown in the figure, the prism-equipped lens 18 is housed in a lens barrel 23 with a gear 22 carved around its periphery and open at the top and bottom. The lens barrel 23 has a side surface of the gear 22 formed in an annular portion 24a formed on the upper end surface of the cylindrical holder 24.
By placing it on the holder 24, it is rotatably supported by the holder 24, and a pulse motor 26 is meshed with a gear 22 formed on the periphery of the holder 24 via an intermediate gear 25.

As shown in FIG. 1, the pulse motor 26 adjusts the inclination angle θ (θ) by an amount corresponding to the inclination angle θ (θ゛) of the image calculated by the CPU 21 based on the command from the CPU 21 as a calculation means.
”), the prism-equipped lens 18 is rotated around the holder 24 in response to the rotation.

When the prism-equipped lens 18 rotates, the image projected on the screen 1 rotates, and as a result, the image projected on the screen is automatically rotated to a normal angle and corrected.

The focusing function of the prism-equipped lens 18 can be performed by a focus dial 27. That is, the helical gear 2 provided at the tip of the shaft of the focus dial 27
8 and a helical gear 29 provided on the outer periphery of the holder 24 are in mesh with each other, and the inside of the helical gear 29 is a helicoid, and when the focus dial 27 is rotated, the helical gear 29 rotates. The holder 24 reciprocates in the direction of arrow C (optical path direction). This movement causes the prism-equipped lens 18 to move in the optical path direction, and the image is focused.

FIG. 7 shows a flowchart illustrating automatic correction of image tilt in the above-mentioned microfilm reader. First, when the desired frame number is set by operating the control unit 4, the film encoder counter (not shown), which counts up or down depending on the direction of rotation of the encoder roller 10a, is cleared (Sl), and the film is searched while running. (S2). Then, when the frame immediately before the target frame passes through the projection position (S3)
, side sensors α, β (α°, β°) become ready for sensing, then one side sensor α, β (α゛,
When β゛) detects the image side (S4), the film encoder counter changes the other side sensor β, α(β゛, α°
) until the side of the image is detected (3
5-S7).

When the image search sensor detects that the target frame has reached the projection position (S8), the film advance is stopped.
9) The CPU 21 receives the count data of the film encoder counter and the two side sensors α, β (α”, β°
) calculates the image tilt angle from various quantities such as the interval between (SIO,
5it). Then, based on this calculation result, the pulse motor 26 is driven to automatically correct the tilt of the image on the screen 1 (S12).

In the above embodiment, the image correcting means for rotating the image on the screen is composed of a lens with a prism and a motor for rotating it, but it may also be configured to rotate the entire roll film carrier section. good.

Further, in the embodiment, only two side sensors for detecting the side edges of the image are provided, but it goes without saying that three or more side sensors may be provided. Especially if a large number of sensors are arranged in a matrix,
The inclination angle of the image side can be immediately determined from the detection signal of each sensor without performing calculations as in the above embodiment.

Further, in the embodiment, an example was shown in which a roll film was used as the microfilm, but it goes without saying that the present invention can also be applied to a reader using a fish film or an aperture card.

As explained above, according to the microfilm reader of the present invention, even if the image imprinted on the microfilm is tilted from the normal angle, it can be automatically read without requiring any special operation by the operator. It has the effect of being able to correct the image to a normal angle and display it on the screen, making it extremely useful.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the circuit configuration of a microfilm reader as an embodiment of the present invention, FIG. 2 is a schematic diagram showing the internal configuration of the microfilm reader, and FIG. 3 is a diagram showing the arrangement of side sensors. , FIGS. 4(a) and 4(b) are diagrams explaining the detection operation of the image side by the side sensor, FIG. 5 is a diagram showing the configuration of the prism-equipped lens, and FIG. 6 is an external view of the microfilm reader. FIG. 7 is a flowchart illustrating the image tilt angle correction operation performed by the microfilm reader. 18... Image correction means (lens with prism), 20.
...Image search sensor, 21...Calculating means, α, β, α
゛, β''...Side sensor. Fig. 1 Fig. 2 Fig. 3 Fig. 4 (a) (b) Fig. 5

Claims (3)

[Claims] (1) An image retrieval sensor that detects when a desired image among the many images imprinted on the microfilm has reached the projection position, and at least two points on the sides of the image imprinted on the microfilm. A side sensor for detection, a calculation means that takes in the detection results from the side sensor and calculates the amount of tilt with respect to the normal angle of the image imprinted on the microfilm, and an amount of tilt determined by this calculation that is displayed on the screen. and image correction means for correcting the image inclination angle by rotating the image projected on the image in the opposite direction. (2) the microfilm is a roll film,
Claim (1) characterized in that the image search sensor detects a flip mark provided on the roll film in correspondence with the image, and detects that the desired image has reached the projection position. Microfilm reader described in . (3) The image correction means is a lens with a prism provided in the projection optical path for projecting the image on the microfilm onto a screen, and a motor that rotates the lens by a predetermined amount based on a command from the calculation means. A microfilm reader according to claim (1).