KR880000950Y1 - Color television camera having a color separation crossing striped filter - Google Patents

Abstract

No content.

Description

Color TV Camera with Cross-Color Decomposition Starlife Filter

1 is a partial plan view of a cross color separation stripe filter installed in a light path of a color television camera.

2 and 3 are partially enlarged plan views of the cross-sectional color separation stripe filter of FIG. 1 for explaining the construction principle of the first embodiment of the present invention.

4 is a schematic diagram showing a simple structure of a color television camera according to the present invention.

5 and 6 are partially enlarged plan views of the cross-sectional color separation stripe filter of FIG. 1 for explaining the construction principle of the second embodiment of the present invention.

7 is a partially enlarged plan view of the cross-sectional color separation stripe filter of FIG. 1 for explaining the construction principle of the third embodiment of the present invention.

8 is a schematic diagram showing a simple structure of a color television camera of a third embodiment according to the present invention.

* Explanation of symbols for main parts of the drawings

F: Crossover color separation stripe filter T: Imaging element (tube)

Y, C, W: Color Stri K ₁ , K ₂ : Optical Filter

A: afocul lens system M: master lens system

The present invention relates to a color television (video) camera of the present invention, and more particularly, to a color television camera provided with a cross color separation stripe filter in a light path.

Color television camera (hereinafter, TV is abbreviated as TV) configured to obtain a multiplexed color television signal as an output signal by using a color separation stripe filter having a predetermined pattern in the light path to the photoelectric conversion surface of the imaging tube. In the output signal of the imaging tube, a signal having a spatial frequency corresponding to the repeatedly arranged fine color stripes of the color separation stripe filter provided in the light path between the subject and the photoelectric conversion surface of the imaging tube is generated in a modulated form by the color signal. do.

Therefore, there is a problem that interference occurs between a signal having a predetermined spatial frequency according to the repeatedly arranged fine color stripes of the above-mentioned color separation stripe filter and a signal obtained from a subject, thereby causing bit interference on the reproduction screen.

To date, there have been proposed Japanese Patent Publication Nos. 43-1910, Japanese Utility Model Publication No. 47-18688, and the like proposed to solve the above-mentioned problems of bit interference. In the former case, an optical image of a subject having a specific pattern is given to the photoelectric conversion surface of the imaging tube by using a double-sided convex lens, a phase grating, or the like, in the latter case. Using a flat plane of transparent anisotropic material with birefringence (such as a crystal plate) as an optical interdigital filter, the spatial frequency of the repeated fine color stripes of the color separation stripe filter and the The photoelectric conversion surface of the imaging tube under the state that the optical image of the subject having a specific pattern is defocused only in the scanning line direction so that several times the frequency is peak attenuated and the even frequency of the spatial frequency and the zero spatial frequency are the transmission areas. Was given to. In this way, the above-mentioned bit disturbance of the reproduction screen has been eliminated or reduced.

However, the above-mentioned solution is effective only in the case of the color separation stripe filter configuration in which the color stripes of the filter extending in the vertical direction are constantly arranged in a predetermined repeating order in the scanning line direction (horizontal direction), and the color separation stripe filter In the case of the cross type, since the number of patterns of the subject causing the bit obstruction on the reproduction screen in relation to the pattern of the cross color separation stripe filter is one or more, it is possible to satisfactorily eliminate or reduce the bit interference on the reproduction screen. There was no.

The present invention is proposed to eliminate the drawbacks and drawbacks of conventional color TV cameras having cross color separation stripe filters.

Accordingly, it is an object of the present invention to provide a color TV camera, which does not cause bit interference by a cross color separation stripe filter.

According to the present invention, one or more optical filters and aperture stops are additionally installed in the light path of the TV camera. The optical filter has a characteristic of defocusing a predetermined amount in a predetermined direction, while the hole of the aperture stop makes the defocus due to lens aberration of the TV camera effective in the predetermined direction.

According to the present invention, a color TV camera for generating an electrical output signal representing an image of a subject, comprising: a lens system, an imaging device responsive to light applied through the lens system to generate the electrical signal, and the color A predetermined set of two sets having different cross-directions used for forming a pattern image of the cross-type color separation stripe filter on the photoelectric conversion surface of the image pickup device, having a cross-type color separation stripe filter disposed in the light path of the TV camera. In the repeating arrangement of any one of a plurality of color stripes in the repeating arrangement of the color stripes of the color, when the length of the scanning line direction on one color stripe is set to Pn, the direction substantially perpendicular to the extension direction on the color stripe To produce a blurred width of the length corresponding to the length Pn with respect to the optical conversion surface of the image pickup device. The learning filter is provided on the light path to the photoelectric conversion surface of the imaging element.

A color TV camera for generating an electrical output signal representing an image of a subject according to the present invention, comprising: a lens system, an imaging device responsive to light applied through the lens cyste to generate the electrical signal, and the color TV A predetermined set of two sets each having a cross color separation stripe filter disposed in an optical path of a camera and used to form a pattern image of the cross color separation stripe filter on the photoelectric conversion surface of the image pickup device. In a repeating arrangement of color stripes of any color stripe in a color stripe arrangement, a length in the scanning line direction of one color stripe is set to P _v , and is a direction perpendicular to the scanning line direction on the color stripe. When the length of Pv is Pv, the height of the bottom side of the length of Pn and 1/2 of the length of Pv in the scanning line direction Is a direction in which at least one diagonal direction is almost blurred in this simulated rectangular shape, thereby producing an optical blurred effect almost corresponding to the width at which the diagonal length is blurred on the photoelectric conversion surface of the image pickup device. An optical filter is provided in the light path to the photoelectric conversion surface of the imaging device.

A color TV camera for generating an electric output signal representing an image of a subject according to the present invention, comprising: a lens system, an imaging device responsive to light applied through the lens system to generate the electric signal, and the color TV A cross color separation stripe filter disposed in an optical path of a camera is provided to form a pattern image of the cross color separation stripe filter on the photoelectric conversion surface of the image pickup device. A repeating array image of color stripes is used, and holes are formed such that the image formed on the photoelectric conversion surface of the image pickup device is blurred by a predetermined amount in a specific direction relative to the pattern of the cross-color decomposition stripe filter by lens aberration of the lens system. An aperture stop is provided in the light path to the photoelectric conversion surface.

The objects and features of the present invention will become more readily and apparent from the detailed description of the preferred embodiments associated with the accompanying drawings.

Hereinafter, the present invention will be described with reference to the drawings. In the drawings, the same or corresponding elements are denoted by the same reference numerals.

In order to more easily understand the object and features of the present invention, before describing the present invention, the configuration and operation of the cross-type color separation filter used in the conventional color TV camera will be described.

FIG. 1 is a partial plan view of an example of the cross-sectional color separation stripe filter F. In FIG. 1, the S-S line represents the direction of the scan line, and the N-N line represents the direction orthogonal to the scan line direction S-S. Reference symbol W denotes a filter stripe capable of transmitting all color light (color stripe W), Y denotes a filter stripe capable of transmitting yellow light, and C denotes a filter stripe capable of transmitting blue light. Each color stripe W, Y and C has a stripe width indicated by the reference symbol P. The color stripes Y and W are alternately arranged in parallel so that their extension directions are the same as the arrow R direction rotated clockwise by an angle β from the line N-N direction orthogonal to the scan line direction S-S. The color stripes C and W are alternately arranged in parallel with each other so that their extending directions are in the same direction as the arrow B direction rotated counterclockwise by an angle α from the above-mentioned line N-N direction.

Therefore, by repeating the arrangement of the two color stripes which differ in the extending direction of the two sets described above, W, G, W, G,... An alternate color separation stripe filter F in which the repeating filter pattern of and Y, C, Y, C repeating filter patterns in the scanning line direction alternately appear in the direction orthogonal to the scanning line direction is formed. In the above figures, G represents the green filter part.

In the cross-sectional color separation stripe filter F of FIG. 1, the horizontal pitch of the filter pattern in the scan line direction SS and the vertical pitch in the direction NN perpendicular to the scan line direction SS are the length Pn in the scan line direction and perpendicular to the scan line direction. The phosphorus direction is Pv, and the color stripes W, C or Y each have a width P. In many cases, that is, under the condition that a cross-color decomposition stripe filter F composed of a filter pattern having a horizontal pitch Ph and a vertical pitch Pv is applied to the photoelectric conversion surface of the image tube, it has a width Ph in the pre-scan direction and is perpendicular to the scan line direction SS. The black-white vertical stripe pattern extending in the in-direction NN is provided to the photoelectric conversion surface of the image pickup tube by the subject; When the space between the scanning lines scanning the surface of the photoelectric change surface is half of the vertical pitch Pv of the filter pattern, the subject image applied to the photoelectric conversion surface of the image pickup tube has a width of Pv / 2 in the NN direction and extends in the scanning line direction SS. For black-white lateral stripe pattern; The subject image is a black and white inclined stripe extending in the B or R direction in which the color stripe extends and having a width in a direction perpendicular to the extending direction, and reproduced in these various cases applied to the photoelectric conversion surface of the imaging tube. Bit interference occurs on the screen.

In the above-described cases where bit interference occurs, bit interference generated by applying the vertical-stripe pattern of the subject to the photoelectric conversion surface of the imaging tube can be satisfactorily eliminated by conventional means, but bit interference caused by other reasons Can not be removed by the conventional means described above.

Generally speaking, the characteristic vertical-stripe pattern of the subject causes bit interference on the reproduced screen because it often causes the above-mentioned bit interference on the picture reproduced in the vertical stripe pattern, and other patterns do not cause such bit interference. A color TV camera manufactured by the conventional means described above can be used in practice so as not to generate a pseudo color signal. However, since another requirement that is essential for picture quality is proposed today, eliminating bit interference using only conventional means is insufficient to satisfy this requirement. In other words, there is a need for a better way to improve screen quality.

The present invention solves the above-mentioned problems by providing one or more optical filters and one aperture stop in the light path of a TV camera having a cross color separation stripe filter.

In the first and second embodiments to be described later, one or two optical filters are used to defocus an image of a subject in a predetermined amount and a predetermined direction, and in the third embodiment, a color TV camera is used by using a aperture stop. The lens aberration is used to defocus a predetermined amount in a predetermined direction.

The optical filter used in the first embodiment causes defocusing or blurring in the direction perpendicular to the extension direction of the color stripe on the photoelectric change plane of the image pickup tube. Wherein the length or width of the blur is associated with Ph, where Ph is a repetitive color stripe of a plurality of given colors selected from a repetitive phase of two sets of repetitive color stripes extending in different directions with a number of different colors. It is the length in the scanning line direction on one color stripe in the image. Hereinafter, the optical filter used in the first embodiment of the color TV camera according to the present invention will be described in detail.

2 and 3 show an optical filter installed in the light path to the photoelectric conversion surface of the imaging tube in the first embodiment of the color camera according to the present invention, and defocusing direction on the subject appearing on the photoelectric conversion surface of the imaging tube. And a view for explaining the width. This figure is an enlargement of a portion of the cross-sectional color separation stripe filter of FIG. 1, with reference numerals W, Y and C being color stripes, S-S being in the scanning line direction, and N-N being in a direction perpendicular to the scanning line direction S-S.

The cross color decomposition stripe filter F is composed of two sets of color stripe devices, namely, color stripes Y, W, Y,... A set of color stripes, and color stripes C, W, C,... Extending in the direction indicated by arrow B as described above. It consists of a set of different colored stripes. Each color stripe Y, W, Y,... Width extending in the P direction and extending in the R direction. Is inclined clockwise by the angle β from the direction N-N perpendicular to the scanning line direction S-S, and each of the color stripes C, W, C... Are inclined counterclockwise by α each from the direction N-N perpendicular to the scan line direction S-S.

The length of each color stripe W, Y and C of width P in the scanning line direction SS Ph may be represented as Ph = P / cosβ in FIG. 2 in relation to each stripe Y and W extending in the R direction and Ph in FIG. 3 in relation to each stripe C and W extending in the B direction. It may be expressed as = P / cosα. In FIG. 2 (or FIG. 3), the line EJ is a line indicating a direction perpendicular to the extending direction R (or β) of the specific color stripe. Represents the width P of each color strap. These angles can be expressed as θ because the above-described α and β of the cross-color decomposition stripe filter F are generally equal to each other.

In the first embodiment of the present invention, an optical filter capable of defocusing a subject image formed on the photoelectric conversion surface by a predetermined amount in a line EJ direction, that is, a direction perpendicular to the extending direction of each stripe is provided. The defocus width in the above-mentioned direction by the above-described optical filter provided in the first embodiment and installed in the light path to the photoelectric conversion surface is = Ph or = Ph / cosβ (or = Ph / cosα). Furthermore, the defocus width can be chosen as a value between Ph and Ph / cosβ, where β = α if necessary.

In the line EJ direction, when the defocus width on the object formed on the photoelectric conversion surface of the imaging tube by the optical filter described above is EH = Ph, the black and white inclined stripe extending in the direction in which the color stripes extend is photoelectric conversion of the imaging tube. Even if applied as a subject image on the surface, bit interference does not occur. By the above-described optical filter, the defocus width in the direction of the line EJ with respect to the subject image on the photoelectric conversion of the imaging tube = Ph / cosβ or Even in the case of = Ph / cosα, even if the black and white vertical stripe pattern extending in the direction NN orthogonal to the scanning line direction SS forms an image on the photoelectric conversion surface of the imaging tube, no bit interference occurs in the reproduced screen. Moreover, in the latter case, even if the black and white oblique stripe stripe pattern extending in the same direction as the extension direction of the color stripe is formed on the photoelectric conversion surface of the image pickup tube as the object image, the bit interference is significantly reduced.

Like the optical filter described above, an optical filter may be provided that provides a predetermined defocusing width in a direction orthogonal to the color stripes extending in the R direction. If one method is selected from these two methods in which an optical filter is provided, it is desirable to provide an optical filter that provides a given defocusing width in a direction orthogonal to the color stripes extending in the R direction in view of human visual characteristics.

4 is a simplified structural diagram of a first embodiment of a color TV camera according to the present invention (FIG. 4 also shows a second embodiment of the present invention). In FIG. 4, T is an imaging device (e.g., an imaging tube, a solid-state imaging device), F is a cross color separation stripe filter, Z is a zoom lens system, A is an achill lens system, M is a master lens system, and K ₁ ( K ₂ ) is an optical filter used in the first embodiment of the present invention. The optical filter K ₁ (K ₂ ) can defocus an image of an image formed on the photoelectric conversion surface of the imaging tube in the direction of the line EJ (direction perpendicular to the extension direction of each color stripe) by the predetermined amount described above.

In FIG. 4, one of the two optical filters is shown in dashed lines, since the optical filter used to implement the present invention may be provided at one or two of the K ₁ and K ₂ positions in FIG. In the position K _{1 of} FIG. 4, an optical filter of a kind such as a correction filter, a biconvex lens, a phase grating, a bisprism, or the like can be used if it possesses the above-mentioned characteristics. However, it is necessary to provide another optical filter than the correction filter as used at the K ₁ position in FIG.

In the implementation of the first embodiment, the above-mentioned optical filter K ₁ (K ₂ ) is also used so that the auxiliary optical filter or the optical device can also eliminate the bit interference occurring in the reproduction picture caused by the stripe pattern in the specific direction of the subject. May be used in addition to

The defocusing direction and width by the optical filter used in the first embodiment may be changed so that defocusing is realized in another way. In the second embodiment of the present invention, the defocusing direction and width are changed differently from those in the optical filter used in the first embodiment.

Therefore, Figs. 5 and 6 show the defocusing direction and width given for an image to be imaged on the photoelectric conversion surface of the imaging tube by the optical filter installed in the fruit path of the light conversion surface of the color TV camera imaging tube according to the present invention. It is a figure for demonstrating. These figures are partially enlarged views of the cross-color decomposition stripe filter shown in FIG. 1, where W, Y, and C are color stripes, S-S is the scan line direction, and N-N is the direction orthogonal to the S-S scan line direction.

As described above with reference to FIG. 1, the cross color separation stripe filter has two sets of color stripe arrangements, that is, a set of color stripes Y, W, Y.... Is the direction R, and another set of color stripes C, W, C... Is the direction B. Each color stripe Y, W, Y ... in the direction R and width P; Is inclined clockwise by the angle β from the direction N-N orthogonal to the scanning line direction S-S, and each of the color stripes C, W, C,... Is inclined counterclockwise by the angle α from the direction N-N orthogonal to the scan line direction S-S.

The length DE = Ph of the scanning line direction SS of the color stripes W, Y and C of width P can be expressed by the formula Ph = P / cosβ for FIG. 5 with respect to each of the stripes Y and W of the extending direction R. And with respect to each stripe C and W in the extending direction B, can be expressed by the formula Ph = P / cosα for FIG.

For the sake of simplicity, assuming that α = β, each color stripe length Pv to NN, which is effective for the scan line direction SS, is given by Pv = Ph cotβ = Ph cotα (α = β in a cross-color decomposition stripe filter). .

The above-mentioned Ph is the pitch of the cross-color decomposition stripe filter F- in the scanning line direction SS (horizontal side pitch), and Pv is the pitch of the cross-color decomposition stripe filter F in the direction NN perpendicular to the scanning line direction SS (vertical side pitch). to be.

In FIGS. 5 and 6, consider a rectangular DEGH having a base side in which the scan line direction S-S is Ph and a vertical side, that is, a base side having a length of Pv / 2. The image of the subject can be imaged on the photoelectric conversion surface of the imaging tube, and when an optical filter whose blur defocusing width corresponds to the diagonal EH of the rectangular DEGH is provided in the light path of the photoelectric conversion surface of the imaging tube, The image of the subject will be defocused by the horizontal pitch Ph in the scanning line direction and by the vertical pitch Pv in the direction orthogonal to the scanning line direction.

Since the spacing between adjacent scanning lines in the image pickup device is selected to be half of the above-described vertical pitch Pv, the vertical stripe pattern having a pitch of Ph by providing an optical filter having the above-described characteristics in the light path along the photoelectric conversion surface of the image pickup tube The bit interference occurring in the reproduced picture due to the subject and the horizontal stripe pattern subject having the pitch of Pv / 2 is well removed.

The optical filter used in the color TV camera of the above-described second embodiment according to the present invention may be positioned at the K ₁ and K ₂ positions in FIG. 4 in the same manner as in the first embodiment. That is, the optical filters K ₁ and K ₂ used in the second embodiment have the horizontal image pitch Pv in the scanning line direction SS in the scanning line direction SS by the horizontal pitch Ph and the direction NN orthogonal to the scanning line direction SS in the image pickup surface of the imaging tube. You can defocus by half.

In the K ₂ position of FIG. 4, an optical filter of a kind such as a quartz filter, a biconvex lens, a phase grating, a biprism, or the like may be used if it has the defocusing characteristics described above. However, the correction filter may not be used as the optical filter used at position K ₁ of FIG. The auxiliary optical filter or the optical means can be used in addition to the above-described optical filters K ₁ and K ₂ in the same manner as in the first embodiment, so that it is generated in the screen reproduced by the stripe pattern in the specific direction of the subject. Bit interference can be eliminated.

Although in the first and second embodiments described above, one or more optical filters have been used to defocus an image of a subject in the above-described manner, a hole stop may be used instead of one or more of these optical filters. The lens used to image the subject on the photoelectric conversion surface of the imaging tube has various aberrations, and it is already known that a blur occurs on a subject formed on the photoelectric conversion surface of the imaging tube according to the degree of aberration of the lens. Since the aperture can be adjusted according to the open state, it is also known that a single lens is limited in the adjustment of the aperture stop so that the degree of defocusing is low.

As described above, in view of the fact that blur occurs due to the aberration of the lens, the third embodiment of the present invention imparts a direction to the blurring of the image due to the aberration of the lens and It has been proposed to reduce or eliminate bit interference due to interference between patterns of a subject. For this purpose, the shape of the aperture stop installed in the light path of the color camera is given a direction.

FIG. 7 is an enlarged view of the cross-sectional color separation stripe filter of FIG. 1, and S-S, N-N, Y, C, W, P, Ph, Pv, α, β and the like are the same as those of FIG.

The pattern of the subject causing the occurrence of bit interference in the picture reproduced by the pattern of the cross-color decomposition stripe filter F is a vertical stripe pattern with a pitch of Ph, a pitch of Pv / 2 and a side as described with reference to FIG. Directional stripe pattern, and oblique stripe pattern extending in the direction R or B with pitch Pv / 2. The width and direction of the blur given to the subject image on the photoelectric conversion plane of the shooter in order to remove the interference generated in the reproduction screen due to the above-described various patterns of the subject image are the width of DE = Ph in the scanning line direction SS, and the scanning line The width of DK = Pv / 2 in the direction NN orthogonal to the direction SS, the width of EH = Ph in the direction orthogonal to the color stripes extending in the direction R, and the width in the direction orthogonal to the color stripes extending in the direction B This is DM = Ph.

Although it is necessary to defocus the image in the various directions described above to completely eliminate bit interference in the reproduction picture, the necessary resolution is not obtained when defocusing in various directions is performed.

Therefore, in the third embodiment, when the predetermined blur width and direction for the subject image are displayed by the line segment of FIG. 7, the predetermined blur for the image of the subject corresponds to one of DE, DK, EH, and DM. The bit interference due to the specific pattern of may be removed, or the predetermined blur for the subject image is set so that the bit interference due to the specific vertical stripe pattern of the subject image is removed, corresponding to the EJ or DQ, and the direction If the bit interference due to a particular oblique stripe pattern of the subject image extending to R or B is eliminated, or if the image of the subject has a specific vertical stripe pattern and a lateral pattern, then the two bit interferences cause blurring of the subject image. It is removed in such a way as to correspond to it.

In order for the blur having the above-described directions and widths to be generated in the subject image, a hole stop having a drawing shape which provides a period of minimum confusion extending in the required direction is used.

In addition to the use of the aperture stop described above, means for capturing light through the center of the lens (e.g., a mask can be provided at the center of the lens, and a point mirror for reflecting light towards the viewfinder side is provided by TTL In the case of a system it may be provided in the pupil of the center of the lens, the splitting ratio of light may be controlled by a half mirror instead of a point mirror, or an ND filter may be provided in the center of the lens instead of the mast described above ) Can be used.

FIG. 8 shows a simplified structure of a color TV camera, and the same reference numerals as in FIG. 4 show the same or corresponding elements. The aperture stop used in the third embodiment is denoted AS, and is located at a given point in the lens system including the Apokill lens system A and the master lens system M of FIG.

As indicated by K ₂ in FIG. 8, the optical filter used in the above FIG. 1 and FIG. 2 embodiments is used in addition to the aperture stop AS. That is, when the optical filter composed of the two convex lenses, the phase lattice plate, the biprism and the like needs to remove the bit interference due to the stripe pattern in the specific direction of the subject image that is not removed by the facility of the aperture stop AS of the third embodiment. It is located in the light path. In other words, the third embodiment is combined with one of the first and second embodiments so that one or more optical filters of the first or second embodiment are used simultaneously with the aperture stop of the third embodiment. Can be.

As described above, in the color TV camera according to the present invention, the conventional problem affecting the color TV camera provided with the cross color separation stripe filter is well eliminated, and the present invention is a color in which bit interference does not occur in the reproduction picture. A TV camera can be provided easily.

The above-described embodiments are only examples of the present invention, and it will be appreciated that various modifications and changes can be made by those skilled in the art without departing from the spirit of the present invention.

Claims (3)

A color television camera for generating an electrical output signal representing an image of a subject, comprising: (a) a lens system, (b) an imaging assistant for generating the electrical signal in response to light imposed through the lens system; c) a cross-sectional color separation stripe filter provided in the light path of said color television camera, each having a repeating array of parallel color stripes extending in different directions and having a predetermined plurality of color repeating color stripes, and (d) Repetition of two sets of predetermined color stripes each having two different mutually extending directions, which are provided on the photoelectric conversion surface of the imaging device and are used to form the pattern image of the cross-sectional color separation stripe filter on the photoelectric conversion surface of the imaging device. When the scanning line length on one color stripe on any one repeating array in the array is Ph, the color stripe phase The collar having a cross-shaped color separation stripe filter of the blurred edge width of a length corresponding to the length of Ph in the direction substantially perpendicular to the extension direction, characterized in that it comprises an optical filter for causing the photoelectric conversion surface of the image pickup device television camera 2. The color television camera of claim 1, wherein said blurred width substantially corresponds to said Ph. The color having a cross color separation stripe filter according to claim 1, wherein the blurring width substantially corresponds to Ph / cos θ, and θ is an angle between a scanning line direction on the photoelectric conversion surface of the image pickup device and a direction to be defocused. TV camera.