JP4568480B2 - Information display device - Google Patents

Description

[0001]
[Industrial application fields]
  The present invention uses information such as images and characters.Can be displayedThe present invention relates to an information display device.
[0002]
[Prior art]
FIG. 30 is a diagram showing an example of an image display device using a spatial light modulator.
In the figure, reference numeral 1 is a light source, 2 is a diffuser plate, 3 is a condenser lens, 4 is a liquid crystal panel as a spatial light modulator, 5 is a projection lens, 6 is a screen, 7 is a liquid crystal panel unit, 8 is a light source drive unit, Reference numeral 9 denotes a liquid crystal panel drive unit.
[0003]
Light emitted from the light source 1 driven by the light source drive unit 8 is converted into uniform light by the diffusion plate and enters the liquid crystal panel 4. The liquid crystal panel 4 is driven by the liquid crystal panel drive unit 9 to display a light and dark pattern according to the image information, and the incident light is modulated by the pattern and is incident on the projection lens 5. The projection lens 5 projects the bright and dark pattern displayed on the liquid crystal panel 4 onto the screen 6 to form an image. In this way, the image displayed on the liquid crystal panel as the spatial light modulator is enlarged and projected on the screen.
[0004]
In general, the element size of a liquid crystal display element is larger than the element size of an imaging element such as a CCD. Therefore, in the same screen size, the number of pixels of the liquid crystal display element is smaller than that of the imaging element. Therefore, in order to display an image obtained using the image sensor on the liquid crystal display element with the same definition, a larger screen size is required, but since the yield deteriorates, the number of pixels equivalent to that of the image sensor is reduced. It is difficult to make a liquid crystal panel.
[0005]
As one solution to the problem, many image display method apparatuses have been filed that display pixels shifted to increase the number of apparent pixels rather than the number of pixels of the spatial light modulator. A technique for shifting pixels using the action of polarizing transmitted light in a liquid crystal element is also known (see, for example, Patent Document 1 and Patent Document 2).
[0006]
  FIG. 31 is a diagram illustrating an example of pixel shifting. The pixels of the projected image are not densely arranged, but are displayed at a predetermined interval from the top and bottom. This figure shows an example in which one pixel shift is performed both vertically and horizontally, that is, one shift is performed. Although there are several combinations of the order of up / down and left / right shifts, for example, the display state shown in FIG. 9A shifts to the display state shown in FIG. Similarly, in the same figure (c), (d)likeAfter the display state changes, the display state again returns to the display state of FIG.
[0007]
When all the pixels are overlapped when the display state is one cycle, the pixels do not overlap and are arranged so that there is no gap. That is, the size of the pixel on the display surface is set to a half of the display pixel pitch. The display pixel size when forming an image with two shifts is set to one third of the display pixel pitch. The same relationship as described above is required for the pixel size and the pixel pitch as the constituent elements of the spatial light modulator.
[0008]
In an image display device using a piezoelectric element as a pixel shifting element, there is an example in which the display problem during pixel shifting is solved by turning off illumination light during the pixel shifting operation (see, for example, Patent Document 3). . However, it is difficult to turn on and off the light source at a high speed by using a lamp, and even with other semiconductor light sources, the on / off operation involves a transient state and the light is shielded all at once, resulting in a large light loss.
[0009]
One operation example of the spatial light modulation element will be described.
The image signal of each pixel constituting the spatial light modulator is updated line by line in pixel column units (or pixel row units). Looking at the time from the start to the end of the update, at the time when the update of the pixel column that started updating first is completed, the end column is in a state where the update is not completed. Further, as soon as the display information update of all the pixels in the column is completed, the image display is started sequentially. Therefore, at the time when the update of the first column is finished and the image starts to be displayed, the display of the image is not started in the last column.
[0010]
In the case of displaying images shifted in such a display method, if the place where the pixels are moving is displayed, the pixels appear to be connected, so that the image is blurred. Therefore, it is preferable that the pixel shift is performed by performing a light shielding process during the image update so that the moving state of the pixel is not displayed.
[0011]
The problem here is that if the pixel shift timing is matched with the update timing of the first column, for example, the pixels that are moved by pixel shift are not displayed for the first column, but the updated display of the image is started in the last column The movement of the pixel is started before being performed. At that time, since the light is not shielded, the moving pixel can be seen. Or, conversely, if the pixel movement timing is matched with the update timing of the tail address, the pixel movement of the head address is now visible. In any case, it is necessary to prevent the image of the moving pixel from being displayed.
[0012]
FIG. 32 is a diagram showing a part of the spatial light modulation elements arranged in a matrix.
FIG. 33 is a view showing a part of the spatial light modulation elements arranged in a honeycomb shape.
In both figures, reference numeral 11 denotes a spatial light modulator, and 12 denotes a pixel column.
When the pixels are shifted and displayed at a speed higher than the normal frame frequency, there is an effect that the pixels are visually multiplied. When the display is shifted, the information density of the display image can be doubled by changing the information of the individual pixels to be moved and displayed. Such a technique for shifting and displaying pixel images is often referred to as pixel shifting or wobbling.
[0013]
As shown in FIGS. 32 and 33, when an image of each pixel is projected and displayed using a spatial light modulation element composed of a plurality of pixels arranged in a matrix or honeycomb and independently modulated. In addition, by using a wobbling technique or a pixel shifting technique for the optical device that projects the pixel image, the pixel image is shifted and projected, so that the apparent number of display pixels is larger than the number of pixels of the spatial light modulator. Technology is known.
[0014]
[Patent Document 1]
Japanese Patent No. 2813041 (2nd page)
[Patent Document 2]
Japanese Patent Laid-Open No. 7-36054 (pages 3 to 4, FIG. 6)
[Patent Document 3]
JP 2001-356411 A (page 8, FIG. 4)
[0015]
[Problems to be solved by the invention]
The problem with pixel-shifted display is that the image is blurred when the image of the pixel is displayed while the pixel is moving. Therefore, it is desirable to process so that the moving pixels are not displayed. For non-display, it is necessary to prevent light from the pixels from reaching the projection surface.
[0016]
Although the lamp light source is most often used in the above-described processing, it is difficult to turn on and off the lamp light source at high speed. Since the frame frequency of a normal display device is about 60 Hz, it is difficult to turn on / off the lamp light source faster than this. However, according to the method of shielding the lamp illumination light by the optical means, the same effect as when the lamp light source is effectively turned on / off can be obtained. However, this alone cannot hide the moving pixels.
[0017]
This is because display information of all pixels on the spatial light modulation element may not be updated and displayed at the same time when performing pixel-shifted display. That is, in the case where pixel information is updated line-sequentially in units of pixel columns, each of the period during which information is displayed, the period during which information is updated, and the period during which updated information is displayed are all Pixels do not match. For this reason, the problem that the moving pixels are displayed or the light is unnecessarily shielded by simply shielding the illumination light remains.
[0018]
FIG. 34 is a schematic diagram illustrating the relationship between the information update timing of the pixel column and the information update period.
In this figure, the vertical axis represents the pixel column position, the horizontal axis represents time, and the pixel column information update period is indicated by hatching. Information is updated when the pixel column whose information is to be updated moves from top to bottom in the figure. It shows how the timing is delayed. The information update start time for the first pixel column is T1 and the end time is T2, the information update start time for the last column is T3, and the end time is T4. T3> T1 and T4> T2. Diagonal lines T1-T3 are lines connecting timings at which the first pixel of the pixel column starts updating information.
[0019]
Here, it is preferable that the pixel shift period is during the information update period, and if the pixel display is moved after the information update is completed, the image appears to be shifted. FIG. 34 illustrates the pixel display movement start time as T5 and the end time as T6.
Hereinafter, for convenience of explanation, the time T3-T1 from the information update start time of the first pixel column to the information update start time of the last column is named update transition time, and the time required for information update is named update required time.
[0020]
It can be seen that the relationship between T5> T3 and T6 <T2 should be satisfied so that the pixel display movement period is in the information update period. However, since the illumination light irradiates the pixels of the spatial light modulator in the pixel display movement period, the pixel image is displayed.
In order to prevent the image of the pixel from being displayed, the illumination light may be shielded so as not to illuminate the pixel during the pixel display movement period.
[0021]
  FIG. 35 is a diagram illustrating a state where light is shielded so that all pixels are not illuminated during a period of time T5 to T6.
  In the same figure, the light-shielded areas at times T5 to T6 are hatched.
  In this wayThereforeLight shielding during the pixel movement period is achieved. However, an area that is not shielded remains in the area during the information update period. The area is indicated by another hatching. Since there is no display information in this area, if the pixel in that state is illuminated, an undesired display may occur.
[0022]
That is, when the liquid crystal display changes from a bright state to a dark state, there is no problem because the liquid crystal element responds relatively quickly, but in the opposite case, there is a delay in response and a little time is required. Therefore, when changing from a dark state to a bright state of a certain gradation, if the image display is started before the predetermined gradation is changed, the gradation change will continue after the display. . In addition, since there is a slight difference in response delay among elements, instantaneous brightness unevenness appears even between pixels that should finally exhibit the same gradation.
[0023]
  FIG. 36 is a diagram showing a state where the shaded area in FIG. 35 is also shielded.
  Both the oblique lines T1-T3 and the oblique lines T2-T4 are included in the light shielding region.
  The light shielding start time is T1, and the light shielding end time is T4.FIG.In FIG. 5, the light shielding area is hatched. If the light is shielded as shown in the figure, the pixel whose information is being updated can be prevented from being displayed.
[0024]
The light blocking time in FIG. 36 is T4-T1, and all the pixels are turned off during the light blocking period. The problem with this shading method is that the time during which the screen becomes dark due to the shading is long. In FIG. 36, the display information is updated at time T2 in the first column of pixels, but is not displayed because it is shielded from light. The displayed time is T4. Therefore, the display of time T4-T2 is cut. Similarly, in the last column of pixels, the update of display information starts at time T3, but since the shading is started at time T1, the display of time T3-T1 is cut.
[0025]
Incidentally, the relationship between the update transition time and the update required time varies depending on the type of liquid crystal element used. In the diagrams shown in FIGS. 34 to 33, the former is shorter than the latter, but the reverse is also possible. The problem in that case is described.
[0026]
FIG. 37 is a schematic diagram showing a relationship between the information update timing of the pixel column and the information update period, which is different from FIG.
In the figure, the reference numerals are the same as those in FIG.
In the figure, the update transition time is longer than the update required time. That is, at the time T2 when the first column finishes updating the information, the information update has been started up to several subsequent pixel columns, but the last column has not yet started the information update. Therefore, in this liquid crystal element, the situation where all the pixel columns are simultaneously updating information does not occur.
[0027]
If an attempt is made to shift a pixel in such a liquid crystal element in a time period from time T5 to T6, the pixel shift is performed to the pixel column being displayed as shown in FIG. The situation does not change no matter where the pixel shift start timing is set.
[0028]
FIG. 38 is a diagram for explaining a state in which the pixel shifting area in FIG. 37 is shielded from light.
In FIG. 38, the light shielding area is hatched.
As is clear from this figure, in addition to the pixels being displayed being shielded from light, a part of the pixel column being updated remains unshielded.
[0029]
FIG. 39 is a diagram showing a state in which all pixels whose information is being updated are shielded from light.
If all of the pixel area whose information is being updated is to be shielded from light, the state shown in FIG. 36 is substantially the same.
Here, for convenience of explanation, a type of spatial light modulator that requires a longer update time than the update transition time shown in FIGS. 34 to 36 is referred to as A type, and is updated from the update transition time shown in FIGS. A type of spatial light modulation element that requires a shorter time will be referred to as a B type.
[0030]
Up to this point, the solution to the problem corresponding to the method in which pixel shifting is performed simultaneously on the entire screen has been described, but a new method of pixel shifting has been proposed. It uses an optical path deflecting element having a number of columns substantially corresponding to the number of pixel columns of the spatial light modulator, and moves the operating column of the optical path deflector in synchronization with the information update of the pixel column of the spatial light modulator. It is a method. According to this method, pixel shifting is performed in units of pixel columns with respect to a pixel column whose information is being updated, and pixel shifting is completed during the information update time.
[0031]
Even in an image display apparatus using such a method, all the screens are simultaneously shielded as long as the light source system is turned on / off in order to shield the pixel column being updated. Inevitable.
Since there are two types of pixel shifting as described above, when distinguishing between them, a method of shifting pixels of all images simultaneously is called a simultaneous shift method, and a method of shifting pixels in units of pixel columns is called a sequential shift method. I will call it.
[0032]
In the spatial light modulator, the present invention does not display an image of a pixel column being updated even when the information update timing is shifted depending on the pixel column, regardless of whether or not the pixel shift is performed. An object of the present invention is to provide an information display device having a light shielding region moving means capable of light shielding with high light use efficiency and high light shielding accuracy.
[0033]
[Means for Solving the Problems]
  According to the first aspect of the present invention, it is composed of a plurality of pixels that can be independently modulated and controlled.The image signal of each pixel is updated line by line in units of pixel columns or pixel rows.The information display device that displays an image of the spatial light modulation element includes a light shielding unit that shields the pixel area so that at least the pixel area whose information is being updated is not displayed.
  This shading meansIs a light valve,At least the pixel regionIn stripsThe shading area for shadingDepending on the line-sequential update timing of the image signalIt has a light shielding area moving means for moving.
[0034]
  The spatial light modulation elements are two-dimensionally arranged, and the light shielding means can include a light shielding area moving means for moving the light shielding area in synchronization with the movement of the pixel area whose information is being updated.
  The light-shielding area moving means can move the light-shielding area so that only the pixel area whose information is being updated is shielded, and the pixels whose information of the spatial light modulation element is updated are two-dimensionally arranged The position where information update is started can be sequentially moved to adjacent pixel columns.
[0035]
  Spatial light modulatorThe pixel columns from which the information update is started must be multiple pixel columns at the same timeIn this case,Multiple pixel columns that start updating information at the same time are adjacent to each otherYou can alsoThe pixel rows that are updated at the same time are also discretely arranged.it can.
[0036]
  Shading areaAs a similar technique, the moving means may have a rotating prism having the center of the regular polygon as the rotation axis.
[0037]
  As a similar form of the light shielding area moving meansA light shielding member in which the light shielding region and the transmission region are alternately configured in the circumferential direction.Rotating means and illumination light fluxThis is a means for rotating the light shielding member with a spiral light shielding area in the transmission area.In this case,The curve on the inner side of the light shielding region is a spiral shape satisfying r = kθ where r is the distance from the rotation center of the light shielding member, θ is the circumferential angle, and k is the coefficient.Can do.
[0038]
  in this case,The curve outside the light shielding area has a spiral shape satisfying r = kθ + c, where c is a constant.Can be a constantc is the width of the light shielding region in the radial direction of the light shielding memberYou can also.It is characterized by.
  Spatial light modulatorCan also include reduction opticsit can.
  in this case,The reduction optical system is set so that the size of the pixel image is 1 / integer of the pixel arrangement pitch.it can.
[0039]
  Claim 1In the inventionAnd an illumination optical system including an illumination light source, a filter for removing unnecessary components of illumination light, and an integrator optical system in the direction toward the traveling direction of the light beam, and a polarizing beam splitter disposed at the subsequent stage. The linearly polarizing plate is disposed in the light flux between the illumination light source and the illumination light linearly polarized by the linearly polarizing plate is reflected by the polarizing beam splitter, and is disposed at the subsequent stage of the polarizing beam splitter. The color components are separated into RGB components by the separation prism, and the illumination light of each color illuminates three spatial light modulation elements arranged close to the subsequent stage of the color separation prism, and is modulated and reflected by the three spatial light modulation elements. The reflected light is synthesized by the color separation prism, passes through the polarization beam splitter, and reaches a projection optical system. The projection optical system causes each pixel of the spatial light modulation element to Projection displayIs done.
[0040]
  A pixel shifting unit can be disposed between the polarizing beam splitter and the projection optical system, and a relay imaging lens is disposed after the polarizing beam splitter, and the display image of the spatial light modulator is connected in the vicinity of the pixel shifting unit. To imageit can.
[0041]
  Invention of Claim 1Then,A light shielding means having a light shielding area moving means.A light valve consists of three spatial light modulators and a color separation prism.BetweenIn, Close to each spatial modulation element,It is characterized by being arranged respectively.
[0042]
  As a similar technology, light shielding area moving meansIs a device that is made of a transparent member and that is continuously moved by holding an endless belt, which is periodically provided with a light shielding mask portion at a desired width and interval, by a driving roller and a supporting roller.Can do.
  Also mentioned aboveThe spatial light modulation element including the reduction optical system can be a transmissive type, and an auxiliary microlens having a convex lens surface is closely attached to the substrate side of the transmissive spatial light modulation element, and the focal position of the auxiliary microlens Is made to coincide with the focal position of the reduction optical system closer to the substrate.It can be a configuration.
[0043]
  As a similar information display device,At least three illumination optical systems for each of the three primary colors consisting of an illumination light source, a filter for removing unnecessary components of the illumination light, and an integrator optical system, and at the subsequent stage of the illumination optical system, at least in the direction in which the light beam travels The three transmissive spatial light modulation elements corresponding to the three primary colors, a color separation prism for synthesizing the light beams from the three transmissive spatial light modulation elements, and a projection for projecting the synthesized light beams on the screen The illumination optical system illuminates the three transmissive spatial light modulators, and the illumination light modulated by the three transmissive spatial light modulators is a color image by the color separation prism. Is combined with the luminous flux for use and reaches the projection optical system, and the projection optical system projects and displays each pixel of the transmissive spatial light modulator on the screen.You can think of a configuration.
[0044]
  In the aboveThe light shielding area moving means can be arranged adjacent to the latter stage of the integrator optical system, and the light shielding area moving means is composed of a light valve, and includes the three transmissive spatial light modulation elements and the color separation. Each can be arranged between the prisms.
  The light shielding area moving means may be arranged immediately before the pixel shifting means.
[0045]
[Embodiment]
  In the following description, the spatial light modulator is assumed to be a two-dimensional array unless otherwise specified.
  An example of the image display apparatus shown in FIG. 1 will be described.
  In the figure, reference numeral 10 denotes a light shielding device. The other symbols are the same as those shown in FIG. The liquid crystal panel drive unit 9 also serves as a light shielding device drive unit.
  The liquid crystal panel 4 and the light-shielding device 10 may be either one because the light-shielding effect is almost the same even if the front-rear relationship is reversed with respect to the light traveling direction.
[0046]
The liquid crystal panel drive unit 9 controls the display of the liquid crystal panel 4, and simultaneously controls to block a predetermined area of the light blocking device 10 corresponding to the position of the pixel column for information update in synchronization with the information update control. Do.
The relationship between the pixel row for information update and the light shielding area will be described in detail below.
[0047]
  The light shielding by the light shielding region will be described with reference to FIGS.
Information update is performed in units of pixel columns.
  FIG. 2 shows a moment when the first pixel row starts updating information, FIG. 3 shows another moment when the entire image is covered with a light-shielding region, and FIG. 4 shows that the last column of the light-shielding region finishes the information update. Shows a moment before.
  2 to 4, reference numeral 11 denotes a spatial light modulation element, 12 denotes an information update area composed of a plurality of pixel columns, 13 denotes a light shielding area, and A denotes an arrow in the moving direction. In each figure, the pixel columns and the like are drawn larger than the actual ratio. The same applies to the following drawings.
[0048]
  This exampleCorresponds to the case where one of the shift methods is applied to the A type spatial light modulation element, the case where neither of the shift methods is applied, and the case where the simultaneous shift method is applied to the B type spatial light modulation element. ing. Assume that the pixel column of the spatial light modulator 11 is currently being updated. At this time, the light from the light source is incident on the spatial light modulator 11 as a whole, but the light is blocked while the light shielding region 13 is moved in the direction of arrow A by the light shielding means (not shown). The light shielding region 13 is configured to shield light more than the pixel column included in the information update region 12, and shields light to one or more pixel columns adjacent to the pixel column. A portion corresponding to the information update area 12 in the light shielding area 13 is referred to as an effective area.
[0049]
In FIG. 2, in the spatial light modulation element 11 that is displaying an image, for example, information is updated in units of pixel columns from the upper pixel column. It is assumed that the first pixel column starts updating information at a certain moment. Immediately before the start, the light corresponding to the plurality of columns including the first pixel column is blocked by the light blocking region 13 so that the transient state of the pixel column being updated is not displayed on the projection screen. In the same figure, even if there are a plurality of pixel columns whose information is being updated, since the top column has not completed the information update, the light shielding region 13 shields the plurality of pixel columns from light.
As the information update position moves, the light shielding area also moves in the direction of arrow A. Such movement is referred to as scanning for convenience.
[0050]
In FIG. 3, it is a figure which shows the state after the information update area | region 12 reaches the last column.
The information update area 12 extends to all pixel columns, while the light shielding area 13 is also an area including the entire image. When pixel shifting is necessary, it is performed during this period when the entire image is shielded from light. On the contrary, the entire image is shielded from light until the pixel shifting is completed.
When the top pixel row finishes updating the information in this way, the upper edge of the light-shielding region 13 starts to be applied to the upper end portion of the image region, and an image can be displayed sequentially from the first pixel row.
[0051]
  In FIG. 4, when the last column enters the information update operation, the information update has already been completed for some columns from the first column."How many columns lead to the last column?"Is still updating information. The light shielding region 13 shields light up to a row slightly above the uppermost row of the pixel row being updated. Therefore, the light-shielding region 13 is separated from the image region with a slight time difference after the last column finishes updating the information.
[0052]
As described above, the reason for starting the shading earlier than the start of the information update and ending the shading later than the end of the information update is to make the positional accuracy of the movement of the end of the light shielding region 13 gentle. As long as the position accuracy can be kept high, the information update start and the light shielding start, and the information update end and the light shielding end may be performed at almost the same timing. In that case, the image display time can be extended as much as possible, so that the light use efficiency can be improved and a bright image can be provided.
[0053]
As a means for performing the light shielding as described above, for example, there is an optical shutter called a light valve. Light valves using liquid crystals can also be used. Although it is a liquid crystal element similar to the spatial light modulation element, in the case of a light valve, it is a binary control of light and dark that does not have an intermediate gradation, so that the change from dark to bright is suddenly started. Can do.
In the case of an optical shutter or the like, the area that can be shielded is only the same range as the area of the spatial light modulator 11, but for the sake of easy understanding, the light shielding area 13 of a fixed size is shown as moving.
The configuration shown in FIGS. 2 to 4 can also be applied when the spatial light modulator is one-dimensional.
That is, the width in the vertical direction of the light shielding region may be made narrow enough to ensure a desired light shielding time by corresponding to the vertical width of the spatial light modulator.
[0054]
  5 and 6 show the present invention.It is a figure for demonstrating the example of a light-shielding form.
  In both figures, reference numeral 22 denotes an information update area composed of a plurality of pixel columns, and 23 denotes a light shielding area.
  This example corresponds to the case where the sequential shift method is applied to the B type spatial light modulator.
  FIG. 5 shows a state in which a plurality of pixel columns are being updated. At this time, the shading device 10 is a linear area including the information update area 22.That is, a band-like regionIs a light shielding region 23.
[0055]
The information update start column can be configured to always have only one column and a configuration in which multiple columns such as two columns or three columns start information update simultaneously. The latter configuration is referred to as parallel update, and details will be described later. However, even if the information update start is always one column, the next column starts the information update before the information update of that column is not completed. There are always multiple columns except when the last column information update is completed.
[0056]
  BandedThe light shielding region 23 may be configured to shield one or more of the pixel columns adjacent to the pixel column being updated, or may be configured to block only the pixel column being updated. good. The effects obtained by the respective configurations are the same as the effects shown in the above-described embodiment. FIG. 6 shows a state where the information update area 22 has moved to the lower pixel row,BandedThe light-shielding region 23 is also scanned in synchronization therewith, and the pixel row whose information is being updated is shielded from light.
  In the case of the parallel update of the adjacent pixel columns described above, the information update column of the spatial light modulator is selected by skipping the pixel columns. However, for the light shielding region, it is only necessary to increase the light shielding width to a corresponding size.
[0057]
  As a reference example,When the update required time is less than half of the update transition time, the update time of all images can be shortened by setting the information update start pixel row in two stages. The method of simultaneously starting information update in multiple stages is called parallel update.To do. thisIn this case, it is assumed that the number of display pixel columns is an even number.
[0058]
  7 and 8IsAs a reference example2-stage parallel updateExplain the caseIt is a figure for doing.
  FIG. 7 shows a state at a time immediately after the start of information update. FIG. 8 shows a state just before the end of information update.
  In both figures, reference numeral 24 denotes a first-stage information update area composed of a plurality of pixel columns, 25 denotes a second-stage information update area, 26 denotes a light-shielding area corresponding to the first-stage information update area 24, and 27 denotes 2 The shaded areas corresponding to the information update area 25 in the stage are respectively shown.
[0059]
In the case of two-stage parallel updating, all pixel columns are divided into two blocks, an upper half and a lower half, and one column of information update start is assigned to each block. It is arbitrary from which pixel column the information update is started. For example, when the first information update start column moves downward from the upper end in order, the second information update start column is the center of the image. It can be made to move downward from the vicinity. The case where the pixel columns whose information is updated at the same time is separated as described above is called a discrete arrangement.
[0060]
In this way, it is possible to relatively easily control the information update of the spatial light modulator and to simplify the control because the scanning of the light shielding region is continuously moved in one direction.
The pixel rows to be updated in the first and second rows are updated in half the time required to update information in only one row because all the pixel rows are equally divided into two columns. Ends.
By sequentially scanning the light shielding area 26 and the light shielding area 27 in synchronization with the movement of the information update position of each pixel column, an image whose information is being updated is not displayed. Although the light transmission area between the light shielding areas 26 and 27 is a light transmission area, the apparatus configuration can be simplified by integrating the light shielding area between the light shielding areas as a light shielding area.
[0061]
Although the description has been made taking the example of two stages, basically the same can be applied to a plurality of stages of three or more stages. Generally speaking, n and m are arbitrary positive integers, the number of pixel columns of the spatial light modulation element is n × m columns, the number of stages is divided into n stages, and the number of columns for simultaneously updating information is determined as follows. When there are n columns in total from each row, one row is divided into blocks each having m pixel columns, and if information is updated m times, it is 1 / n compared to information updating for each column. In time, each block can finish updating information at the same time. The light shielding area is also scanned by dividing it into n blocks.
[0062]
  9, 10 and 11 are still otherShading exampleIt is a figure for demonstrating.
  FIG. 9 shows a state just before the A surface of the prism faces the light beam. FIG. 10 shows a state in which the A-side is slightly rotated from the state where the A-side is directly facing. FIG. 11 shows a state in which the prism is rotated approximately 45 °. This embodiment corresponds to the case where the sequential shift method is applied to a B-type spatial light modulator.
  In each figure, reference numeral 41 denotes a rotating prism, 42 denotes a light shielding mask, 43 denotes a light shielding area on the spatial light modulation element, A, B, C, and D denote surfaces of the rotating prism, and R denotes a rotation direction of the prism.
[0063]
A rotating prism having a regular polygonal cross section is used. A regular square or regular hexagon is the easiest to use. This method was once used for continuous feed of 8 millicine films.
In the figure, an example using a regular square is shown. The axis of rotation is taken in the direction perpendicular to the paper surface through the center of the regular square. It is assumed that the size of the spatial light modulation element 11 to be illuminated is a square having a side length d. At this time, the size of the rotating prism 41 is set to D in which the length of one side is larger than twice the length of d, for example, and the thickness is substantially equal to d. The size of the light shielding mask and the size of D are determined by the relationship between the ratio of the light shielding time to the time of one field.
[0064]
As shown in FIG. 9, it is assumed that the illumination light beam L comes from the left side of the rotating prism 41. The size of the illumination light beam L is approximately equal to the diagonal line of the rotating prism in the vertical direction and is equal to d in the width direction. The center of the illumination light beam will be referred to as the optical axis X for convenience. When glass having a high refractive index is used as the material of the rotating prism 41, when the surface A of the rotating prism 41 faces the optical axis and is inclined 45 ° by rotation, the outgoing light beam La emitted from the opposing C surface The shift amount of can be made substantially equal to d. However, when the A plane is inclined with respect to the optical axis, the adjacent B plane or D plane is included in the luminous flux, so that the luminous flux is split.
In the case of this embodiment also, it is necessary to provide an antireflection film on each surface of the prism.
[0065]
FIG. 9 shows a state in which the shade of the light shielding mask 43 entering the A surface moves so as to descend from above the spatial light modulation element 11 and begins to shield the leading row. Since the light beam entering the D surface preceding the A surface exits from the B surface facing the surface, it moves so as to descend below the spatial light modulator 11 as indicated by the light beam Ld in the figure. At this time, the light beam Ld has already deviated from the spatial light modulator 11. Since the light beam L incident near the corner of the boundary between the A plane and the D plane is divided and refracted in different directions depending on the plane, the respective emitted lights exit from positions separated from each other. On the other hand, light incident on specific positions on the A surface and D surface separated from each other exits at the corner of the boundary between the B surface and the C surface, and La and Ld are as if they were integrated light beams. Thus, both are continuous.
[0066]
When the rotating prism further rotates and the A surface is slightly inclined after facing the optical axis, the B surface is in a state of being parallel to the optical axis, although the direction of the inclination is opposite, as shown in FIG. It is in a state slightly tilted from. At this time, the light beam L is divided into two.
In the spatial light modulator 11, the light shielding region 43 is moved to the lower half by the light beam passing through the A surface, and the light beam Lb passing through the B surface exits from the D surface, but is considerably above the spatial light modulator 11. It does not contribute to lighting.
[0067]
FIG. 11 shows a state in which the rotating prism 41 is further rotated and the A surface and the B surface are at an angle of 45 ° with the optical axis. At this time, the shade of the light-shielding mask 42 is divided into two at the corner of the boundary between the A surface and the B surface, crosses each other so that they are interchanged, and emits light passing through a position separated from the top and bottom of the spatial light modulator 11. Therefore, the light shielding region 43 is not formed on the spatial light modulation element 11, and such a time zone is a display period for all the pixel columns.
[0068]
In this way, the spatial light modulator 11 is basically constantly illuminated by the continuous rotation of the rotating prism 41, and the light shielding region 43 is directed from the top to the bottom once per rotation of the rotating prism 41. Move to perform partial shading. If necessary, a plurality of light shielding masks can be provided to cope with the multi-stage parallel update described above.
It has been stated that the width of the light shielding mask and the length D of one side of the rotating prism are determined by the relationship of the ratio of the light shielding time to the time of one field of the image display device. But the same is true.
[0069]
The light shielding state as shown in FIG. 3 can be created by making the width of the light shielding mask in FIGS. 9 to 11, that is, the vertical size larger than d.
When D is selected so that the entire spatial light modulation element is in the illumination light beam area when the light shielding area is out of the upper end or lower end of the spatial light modulation element, a desired display period can be secured.
Therefore, the embodiment shown in FIGS. 9 to 11 corresponds to the case where an A type spatial light modulation element is used and the case where the simultaneous shift method is applied to a B type spatial light modulation element.
[0070]
  FIG. 12 shows still anotherShading exampleIt is a figure for demonstrating.
  In the figure, reference numeral 50 denotes a light shielding member, 51 denotes a light shielding mask portion, 52 denotes a light transmission region, and 53 denotes an illumination light beam transmission region. The illumination light beam transmission region 53 is substantially equivalent to the effective region of the spatial light modulator 11. This figure corresponds to the case where the sequential shift method is applied to the B type spatial light modulator.
  The light shielding member is represented by a disk in the drawing, but may be a polygonal shape. The same applies to the following figures.
  The light shielding mask portions 51 and the light transmission regions 52 are alternately arranged with periodicity in the circumferential direction of the light shielding member 50. As the light shielding member 50 rotates in the direction of arrow A, the light shielding mask portion 51 shields the illumination light beam transmission region 53 in order from the top.
[0071]
FIG. 5A shows a state where the upper edge 51 a of the light shielding mask portion 51 is approaching the upper left edge 53 a of the illumination light beam transmission region 53. 53d must be covered.
[0072]
FIG. 4B shows a state where the central portion of the width of the light shielding mask portion 51 is almost at the center of the illumination light beam transmission region 53. At this time, the pixel columns exceeding the predetermined number of pixel columns are shielded from light.
[0073]
FIG. 4C shows a state where the lower end edge 51 b of the light shielding mask portion 51 exceeds the left lower end 53 b of the illumination light beam transmission region 53. At this time, the upper end edge 51 a of the light shielding mask portion 51 must cover the right lower end 53 c of the illumination light beam transmission region 53. The light-shielding mask portion 51 needs to have a width sufficient to cover a predetermined number of pixel rows in one row or a plurality of rows.
Further, FIG. 12 shows an example in which the number of light shielding mask portions 51 on the illumination light beam transmission region 53 is one, but it can be modified so that two or more are provided apart from each other in accordance with the parallel update. .
[0074]
FIG. 13 is a diagram showing a state of light shielding of the pixel row accompanying the movement of the light shielding mask portion.
In the figure, reference numeral 54 denotes a single pixel column.
In this figure, it is assumed that the pixel column 54 is a pixel column on the upper side of the substantially central portion of the spatial light modulator. When the lower end edge 51b of the light shielding mask 51 is rotated in the direction of arrow A, the pixel row 54 is shielded from the left end in order, as shown in FIG. As shown in (c), all the pixels in the pixel column are shielded from light.
When the pixel row 54 is a pixel row below the substantially central portion of the spatial light modulator, the inclination direction of the lower edge 51b of the light shielding mask portion 51 is opposite to the inclination direction of the lower edge 51a shown in FIG. Therefore, the pixel columns are shielded from the right end in order.
[0075]
In FIG. 12, the diameter of the light shielding member 50 is further increased, the width of the light shielding mask portion is increased, and the light shielding mask portion 51 covers the entire illumination light beam transmission region 53 at the same time. This can also be applied to the case where a modulation element is used or the simultaneous shift method applied to a B-type spatial light modulation element. The angle ratio in the rotation direction of the light transmission region 52 and the light shielding mask portion 51 is determined by the relationship between the display period and the light shielding time in one field of image display.
The configuration shown in FIGS. 9 to 13 can also be applied when the spatial light modulator is one-dimensional.
[0076]
  FIG. 14 is still anotherShading exampleIt is a figure for demonstrating.
  In the figure, reference numeral 55 denotes a light shielding member, and 56 denotes a helical light shielding mask portion as a light shielding region. Arrow A indicates the direction of rotation.
  The portion other than the light shielding mask portion 56 of the light shielding member 55 is a light transmission region.
  FIG. 15 is a diagram showing a light shielding state in the illumination light beam transmission region by the spiral light shielding mask portion of the light shielding member. Reference numeral 56a denotes a line-shaped light shielding portion formed by a portion of the light shielding mask portion that covers the illumination light beam transmission region.
[0077]
Both figures correspond to the case where the sequential shift method is applied to the B type spatial light modulator. Since the line-shaped light-shielding portion 56a has curved upper and lower edges, there is an ineffective portion that can cover only a part of the linearly arranged pixel columns. For this reason, the line-shaped light-shielding portion 56a is given a predetermined width in consideration of the invalid portion, whereby a plurality of pixel columns are simultaneously shielded from light.
[0078]
As an equation of the spiral, here, when the radius of the radius from the center of the circle is r, the moving angle of the radius is θ (unit: radians), and k is a constant, the equation r = kθ is given. It shall be determined to satisfy. Since the shading mask portion has a width as described above, the equation defining the outside of the width and the equation defining the inside are different. It is assumed that the above equation is an equation that defines the inner curve.
[0079]
At this time, the equation of the outer curve is r = kθ + c, where c is a constant. c is the width of the light shielding mask portion 56 in the radial direction. The value of c is appropriately determined from the width of the plurality of pixel columns to be shielded from light, the curvature of the spiral, and the margin for mechanical error. If α is set as α = c / k as an angle constant, the above equation can be transformed to r = kθ + kα = k (θ + α), so that the outer curve is phased by an angle α with respect to the inner curve. It will be shifted.
[0080]
As can be seen from FIG. 14, when the line-shaped light-shielding portion 56a is taken, both ends thereof have different distances from the center. Therefore, the center when the line-shaped light-shielding portion 56a is regarded as an arc, the so-called instantaneous center, is the light-shielding member. It is at a position O ′ deviated from the rotational center O of 55. However, O 'is displayed away from the actual position. Therefore, when the center line in the left-right direction of the illumination light beam transmission region is matched with the radial direction of the light shielding member, the light shielding mask line is inclined with respect to the upper and lower sides of the illumination light beam transmission region.
[0081]
In order to prevent this, the center line in the left-right direction of the illumination light beam transmission region is preferably matched with the straight line L1 passing from the instantaneous center O 'through the midpoint of the line-shaped light shielding portion 56a. Since the distance δ between the straight line L1 passing through the midpoint of the line-shaped light shielding portion 56a from the instantaneous center O ′ and the rotation center O hardly changes depending on the portion selected by the spiral, the line-shaped light shielding portion 56a at the outermost peripheral portion of the spiral. All may be substituted with δ0 for.
The illumination light beam transmission region 55 shown in FIG. 15 is set such that the distance from the center line L2 in the left-right direction to the rotation center O is δ0.
[0082]
The relationship between the light transmission region and the light shielding mask portion accompanying the rotation of the light shielding member 55 in the arrow A direction changes from (a) to (d) in FIG. FIGS. 4A to 4D show states every time when the start point 56s of the light shielding mask portion 56 is rotated by 100 ° with the initial position of the rotation angle being 0 ° when the start point 56s coincides with the upper right end 53d of the illumination light beam transmission region 53. ing.
In this embodiment, when the light shielding of the last column shown in FIG. 4D is completed, the process immediately returns to FIG. This corresponds to the case where the pixel column information is continuously updated without a break. For this reason, in FIG. 14, the central angle of the range indicated by the start point 56 s to the end point 56 e of the light shielding mask part 56 that forms a spiral is set to about 330 °. Make the central angle smaller.
[0083]
Since the equation of the spiral is determined as described above, the movement of the intersection of the spiral with respect to the fixed radius becomes constant as the light shielding member 55 rotates at a constant speed. The radius parallel to the left and right sides of the illumination light beam transmission region 53 has an eccentricity δ0 as described above, but since this value is not so large, the speed with respect to the left and right sides of the illumination light beam transmission region 53 can be regarded as substantially constant. .
[0084]
According to this configuration, when the light shielding member 55 is rotated clockwise, the line-shaped light shielding portion 56a applied to the illumination light beam transmission region 53 is sequentially scanned from top to bottom.
By further increasing the diameter of the light shielding member 55 and widening the spiral width of the light shielding mask portion 56, the entire illumination light beam transmission region 53 can be temporarily covered. However, when ensuring the image display period, it is necessary to make the central angle of the range forming the spiral smaller than the example of FIG.
The light shielding member 55 may be provided with a light shielding mask portion 56 on a transparent disk, or may be formed by hollowing only a light transmission region in an opaque disk such as metal.
[0085]
  FIG. 16 is a diagram illustrating a configuration of a light shielding member that can temporarily cover the entire illumination light beam transmission region.
  In the figure, reference numeral 57 denotes a light shielding member, and 58 denotes a helical light shielding mask portion. Also in this figure, the center line in the left-right direction of the illumination light beam transmission region is shifted from the rotation center O by δ0, but the illustration is omitted.did.
[0086]
The curve inside the light shielding mask portion 58 follows the equation of r = kθ + r0 from the point A to the point B in the clockwise direction with the radial direction of the point A as a reference for the angle. r0 is equal to the distance closest to the illumination light beam transmission region 53 from the rotation center O, or slightly smaller than that within the above-described margin range. The radius r1 at the point B is equal to the distance farthest from the rotation center O to the illumination light beam transmission region 53 or slightly larger than the above-described margin range.
[0087]
The outer curve has a configuration in which, for example, the phase of the inner curve is shifted by 180 °.
The arc from the point A on the inner side of the light shielding mask part 58 to the point C counterclockwise is an arc of radius r0. Similarly, from the point B of the outer curve to the point D counterclockwise, an arc having a radius r1 is formed. Therefore, from the point A of the inner curve to the point D of the outer curve counterclockwise, the light shielding mask portion 58 has a constant width equal to c0 = r1-r0.
[0088]
In this example, the equation of the outer curve is r = k (θ + π) + r0 = kθ + kπ + r0. If kπ = c, c is the distance between the inner and outer curves. The radius r2 of the outer curve at point A is set to θ = 0, and r2 = kπ + r0. In FIG. 16, the angle from point A to point B is smaller than π = 180 °, so r1 is smaller than r2. That is, c0 is smaller than c. Therefore, the interval between the two curves is not always the maximum width of the light shielding region.
[0089]
Originally, the light shielding member 57 is moved and the illumination light beam transmission region 53 is fixed. However, in order to facilitate understanding, the light shielding member 57 is shown in the reverse relation in the figure.
Reference numeral 53-1 indicates the position where the light shielding mask portion 58 starts to be applied to the illumination light beam transmission region 53 from the first row, 53-2 indicates immediately before the light shielding mask portion 58 is applied to the last row, and 53-3 indicates that the first row is the light shielding region. 53-4 indicates a position where display is possible, 53-4 indicates a position immediately before the end row is out of the light shielding area, and 53-5 indicates a position where the light shielding mask portion 58 is not covered at all in the illumination light beam transmission area 53. .
[0090]
In the section having the constant width, all the pixel columns in the illumination light beam transmission region 53 are shielded from light. When the image shift is performed by the simultaneous shift method, it is performed when this section covers the illumination light beam transmission region 53. The length of the section having the constant width, that is, the corresponding center angle is set in accordance with the time required for shielding all images.
The light shielding mask portion 58 is interrupted from the point C of the light shielding member 57 to the point B counterclockwise. This section is a section in which the illumination light flux transmission region 53 is not shielded from light, and corresponds to the display period described so far. The center angle corresponding to this section is determined according to the time required for the display period.
[0091]
  FIG. 17 is still anotherShading exampleIt is a figure for demonstrating.
  In the figure, reference numeral 59 denotes a light shielding member, and 60 denotes a spiral light shielding mask portion. A portion other than the light shielding mask portion 60 of the light shielding member 59 is a light transmission region.
  This exampleThen, a plurality of line-shaped light shielding portions are applied to the illumination light beam transmission region 53. This is a configuration corresponding to the three-stage shading region of the parallel update described above.
  The center line in the left-right direction of the illumination light beam transmission region 53 is shifted from the rotation center O by δ0 as in the above embodiment.
[0092]
In the case of this configuration, there are always three line-shaped light shielding portions 60a, 60b, 60c in the illumination light beam transmission region 53, and along with the rotation of the light shielding member 57 in the direction of arrow A, the line-shaped light shielding portions 60a, 60b, 60c moves from top to bottom. However, four line-shaped light shielding portions may be transiently applied. That is, when the effective area of the lowermost line-shaped light-shielding part deviates from the illumination light beam transmission area 53, the effective area of the next line-shaped light-shielding part comes out from the uppermost part. This is a case where the ineffective portions due to the above are applied to the upper and lower ends of the illumination light beam transmission region 53. FIG. 17A shows such a state.
[0093]
Of course, it is easy to configure the illumination light beam transmission region 53 to have two line-shaped light shielding portions at the same time.
This embodiment cannot cope with the simultaneous shift method applied to the A type spatial light modulation element or the B type spatial light modulation element.
[0094]
  18 is still another example.Shading exampleFIG.
  In the figure, reference numeral 61 denotes a light shielding member, and 62, 63 and 64 denote spiral light shielding mask portions.
  The light shielding masks 62, 63, 64 are mutually connected.In the same form,They are 120 ° out of phase with each other.
[0095]
The usage of the light shielding member 61 for the illumination light beam transmission region 53 is substantially the same as the usage of the light shielding member 57 in the above-described embodiment. The difference between the two is the rotation angle of the light shielding member required for the light shielding region to move one step. The light shielding member 57 requires one rotation, whereas the light shielding member 61 requires only one third rotation. Therefore, the number of rotations per unit time of the light shielding member 60 is only one third of that of the light shielding member 57, and the configuration of the rotation mechanism becomes easy.
The configurations shown in FIGS. 14 to 18 can also be applied when the spatial light modulator is one-dimensional.
[0096]
  FIG. 19 shows an image display device to which the present invention is applied.Similar form toFIG.
  In the figure, reference numeral 65 is an illumination lamp, 66 is an optical filter, 67 and 68 are illumination distribution uniformizing means by a pair of fly-eye lens arrays, 69 is a light shielding member as a light shielding device, 70 is a rotating shaft of the light shielding member, and 71 is A light shielding region, 72 is a linear polarization filter, and 73 is a polarization beam splitter (hereinafter referred to as PBS). In this figure, the color synthesis unit and the projection optical system are not shown.
  In this figure, as the light shielding device, the light shielding member 69 shown in FIG. 17 is representatively shown. However, the light shielding device may be a type of spatial light modulation element used in the image display device or a configuration such as a shift method. For example, any of the light shielding devices described so far may be used. This is the same in the following description.
[0097]
The left side of the light shielding area 71, that is, the surface on the light source side is a reflecting surface. Therefore, the light that irradiates the reflecting surface is reflected and returned to the left in the figure to reach the illumination lamp 65. The light returned to the illumination lamp 65 is reflected again by the reflector of the lamp 65 and goes again in the right direction in FIG. That is, it becomes illumination light. Thereby, an optical system means that can be reused as illumination light without losing the light shielded is obtained. As a result, the effect of reducing the light-shielding loss associated with avoiding image blurring due to information updating or pixel shifting can be obtained by means for moving the light-shielding position.
[0098]
  FIG. 20 is still anotherSimilar forms ofFIG.
  In the figure, 74 is a color separation prism, 75 is a spatial light modulator, 76 is a pixel shifting means, and 77 is a projection optical system. In the arrangement shown in the figure, the pixel shifting means 76 is provided between the PBS 73 and the projection optical system 77.
  This figure shows a configuration in which a color synthesis optical system is added to the configuration of FIG.ShowYes.
[0099]
The light beam that has passed through the light shielding device 69 is adjusted to linearly polarized light in a specific direction by the linear polarization filter 72 and enters the PBS 73. All the light beams are reflected on the reflection surface of the PBS and enter the color separation prism 74. The light beams that have passed through the orthogonal color separation reflection surfaces of the color separation prism 74 are separated into three colors and reach the corresponding spatial light modulation elements 75 respectively. In each spatial light modulator 75, the color-specific light beams modulated and reflected by the color-specific image information are rotated by 90 ° in polarization direction before exiting the spatial light modulator 75. Since the polarization direction has changed by 90 °, all the light beams that have returned to the PBS 73 are now transmitted and given a predetermined shift amount by the pixel shifting means 76 to reach the projection optical system.
[0100]
The linear polarizing filter 72 is not an essential element. Even when the light beam incident on the PBS is unpolarized light, only the specific polarization direction is reflected, and the others are transmitted. Therefore, if the transmitted light is absorbed so as not to be reflected or otherwise stray, the linearly polarizing filter 72 can be omitted.
When a spatial light modulator 75 that does not rotate the polarization direction by 90 ° is used, a quarter wavelength plate is inserted between the front surface of each spatial light modulator 75 or between the PBS 73 and the color separation prism 74. You just have to.
[0101]
When this embodiment is applied to the sequential shift method, pixel shifting can be performed with high accuracy when the illumination light beam is a completely parallel light beam. However, in an actual illumination optical system, it is difficult to obtain a highly accurate parallel light beam. If the light beam carrying the image information by the spatial light modulator 75 includes a light beam other than parallel light, the pixel shifting unit 76 shifts the pixels to a part of the light beams from the pixel columns other than the plurality of pixel columns to be shifted by the pixel. The resolution of the image is reduced. Therefore, it is considered that the space between the spatial light modulator 75 and the pixel shifting means 76 is a highly accurate parallel light beam.
[0102]
  FIG. 21 shows yet anotherSimilar form exampleIt is a figure for demonstrating.
  In the figure, reference numeral 78 denotes a microlens array element.
  FIG. 21 shows a microlens array element 78 disposed between the spatial light modulation element 75 and the color separation prism 74 in FIG.
  The microlens array element 78 is a collection of minute lenses individually corresponding to all the pixels of the spatial light modulation element 75. The light beam that enters the microlens array element 78 through the color separation prism 74 is parallel light that is substantially perpendicular to the surface of the microlens array element 78, but includes light beams that deviate from the parallelism.
[0103]
The microlens array element 78 condenses the light beam perpendicularly incident on the surface thereof, guides it to the light reflection surface of the spatial light modulation element 75, and emits the reflected light after modulation in the vertical direction from the surface. Let At this time, the light beam deviating from the parallel is not correctly guided to the light reflecting surface of the spatial light modulator 75, and therefore does not come out as modulated reflected light.
[0104]
  Since the light beams incident on the pixel shifting unit 76 are aligned in the direction perpendicular to the surface of the microlens array element 78 as described above, the column of the shifting operation of the pixel shifting unit in the sequential shift method and the spatial light modulation element The 75 information update pixel columns correspond to each other correctly, and the resolution of the image is not reduced.
  This similar exampleThen, since the light shielding device 69 and the spatial light modulation element 75 are considerably separated from each other, if there is a disturbance in the parallel light beam as described above, there is a possibility that the pixel row being updated cannot be correctly shielded, but the light shielding region is enlarged. By setting, the resolution is not reduced.
[0105]
  FIG.One embodiment of the inventionFIG.
  In the figure, reference numeral 79 denotes a light valve.
  In FIG. 22, a light valve 79 as a light shielding device is disposed between the spatial light modulation element 75 and the color separation prism 74 in FIG. 20, and the light shielding member 69 is omitted. As described above, since the pixel size of the spatial light modulator 75 is half or less than the pixel pitch, even if the light valve 79 cannot be in close contact with the spatial light modulator 75, if it is sufficiently close, The light flux from each pixel of the spatial light modulator 75 is not shattered.
  If the microlens array element 78 as shown in the previous embodiment is overlapped immediately before the light valve 79, both effects can be obtained simultaneously.
[0106]
  FIG. 23 furtherOther similar formsFIG.
  In the figure, reference numeral 80 denotes a relay imaging lens, and I denotes an intermediate image.
  FIG. 23 shows a configuration in which pixels from the spatial light modulator 75 are arranged in a projected light beam for projection display, instead of shielding illumination light, as means for moving the light shielding region on the spatial light modulator 75. . In order to make the light-shielding region coincide with the pixel region to be shielded with high accuracy, the pixels on the spatial light modulator 75 are subjected to intermediate imaging once as an image I in FIG.
[0107]
For example, the relay imaging lens 80 is inserted between the spatial light modulator 75 and the pixel shifting means 76 so that the pixel image on the spatial light modulator is formed as the intermediate image I. In the intermediate image I, the illumination light flux is spatially separated and condensed in units of pixels constituting the spatial light modulator 75, and therefore it can be associated with the pixel shift operation sequence of the pixel shift means 76 with high accuracy. it can. The light-shielding region of the light-shielding device 69 arranged in the immediate vicinity of the pixel shifting means 76 can also be accurately associated with the position of the pixel to be shielded. The pixel shifting means 76 and the light shielding device 69 are shown in this order as viewed in the direction of travel of the light beam. It doesn't matter.
[0108]
  FIG.Is another similar exampleFIG.
  In the figure, reference numeral 81 denotes a light valve as a light shielding device.
  FIG. 24 shows a configuration in which a light valve 81 corresponding to the pixel column of the spatial light modulator 75 is disposed in close proximity to the pixel shifting means 76 as another configuration in which a light shielding device is provided in the projected light beam. The light valve 81 functions as an optical shutter.
  Since the light beam incident on the light valve 81 is a light beam before the pixel shift is performed, if the light beam 81 is placed in the vicinity of the image I of the spatial light modulator 75, the light beam of the pixel row is scattered for the same reason as described above. There is no.
[0109]
  FIG. 25 is still another example.Similar form exampleFIG.
  In the figure, reference numeral 82 denotes a light shielding device, 83 denotes a light shielding belt, 84 denotes a light shielding mask portion, 85 denotes a driving roller, and 86 denotes a supporting roller.
  The light shielding device 82 includes a driving roller 85 connected to a driving shaft (not shown), and a plurality of support rollers 86, an endless belt in which a light shielding mask portion is periodically provided at a desired width and interval on a flexible transparent member. It is an apparatus which is held by and moved continuously in the direction of arrow A. The support roller 86 may be provided with a belt tension adjusting mechanism.
[0110]
  The light shielding mask portion 84 of the light shielding belt 83 is scanned from top to bottom so as to cross the parallel light flux. The light shielding mask portion 84 has a length capable of shielding the width of an illumination light beam transmission region (not shown) and a width capable of simultaneously shielding a plurality of pixel columns. This configuration is shown in FIGS.ExampleIt can correspond to. If the width of the light-shielding mask portion is large enough to shield all pixels at the same time, it is shown in FIGS.Shading exampleCan also be supported.
[0111]
FIG. 26 is a diagram showing a configuration of a spatial light modulation element corresponding to pixel shift used in the present invention.
In the figure, reference numeral 90 denotes a spatial light modulation element, 91 denotes a substrate, 92 denotes a pixel, 93 denotes a microlens array 94, 95 denotes a transparent adhesive layer, 96 denotes a glass plate, and 97 denotes a pixel image.
The microlens array 93 is individually provided so that its optical axis coincides with the center of the pixel 92.
[0112]
The pixel 92 is slightly farther than twice the focal length of the microlens array 93. As a result, the pixel image 97 is formed in the glass plate 96 at a size that is exactly one-half the arrangement pitch of the pixels 92, not half of the pixels 92 themselves. That is, the above arrangement of the microlens array 93 is a reduction optical system for the spatial light modulator. The reduction ratio is not limited to the above, and the size of the pixel image can be generally reduced to an integer, such as one third or one quarter of the pixel arrangement pitch. The number of these is determined by the relationship with the pixel shifting system.
Obviously, if the size of the pixel 92 is set to 1 / integer of the pixel pitch, the above-described reduction optical system is not necessary. Since it falls, it is not generally done.
[0113]
When the focal length of the microlens array 93 is set as described above, the light flux close to the parallel light incident from the front side diverges after being almost converged at the focal position of the microlens, so that the light flux irradiates the entire surface of the pixel 92. .
The spatial light modulator 90 can be used in an optical system as shown in FIGS. However, the object planes of the projection optical system 77 and the relay imaging lens 80 need to be aligned with the plane on which the pixel image 97 is present.
Although the spatial light modulator 90 has been described as a reflection type, it is apparent that the present invention can be applied by configuring an optical system corresponding to the transmissive spatial light modulator.
[0114]
FIG. 27 is a diagram showing an example of an optical system when a transmissive spatial light modulator is used.
In the drawing, reference numeral 87 denotes an auxiliary microlens, 98 denotes a transmissive spatial light modulator including the auxiliary microlens, L denotes incident parallel light, and L ′ denotes outgoing parallel light.
The auxiliary microlens 87 is provided in close contact with the substrate 91 side of the spatial light modulator 90 shown in FIG.
Incident parallel light L incident from the left side of the figure is converged to its own focal position by the auxiliary microlens 87. At this time, the convergent light is set so as to irradiate the pixel 92 without excess or deficiency during the convergence. The focal position of the auxiliary microlens is set to coincide with the focal position on the left side of the microlens 93.
[0115]
With this setting, the incident parallel light is once converged at the focal position after irradiating the pixel, but becomes divergent light as it is and is emitted from the microlens 93. Since the emitted light beam L ′ is divergent light from the focal position of the microlens 93, it becomes parallel light after emission.
Since the relationship between the pixel 91 and the micro lens 93 is determined as shown in FIG. 26, the reduced image 97 of the pixel 91 has the same relationship as that shown in FIG. To form an image. The outgoing parallel light L ′ is a light beam that just includes the pixel image 97 that is a reduced image.
Therefore, if a pixel shifting element is placed after this, a reduced image as shown in FIG. 31 can be obtained on the screen.
[0116]
FIG. 28 is a diagram showing an example in which a transmissive spatial light modulator is applied to a monochromatic image projector. In this configuration, the linear polarization filter 72 and the polarization beam splitter 73 shown in FIG.
The illumination light that has become parallel light through the illumination distribution uniformizing means by the fly-eye lenses 67 and 68 passes through the light blocking member 69 and then enters the auxiliary microlens 87 of the transmissive spatial light modulator 98. The illumination light is emitted with a predetermined refraction.
The light beam L ′ emitted from the transmissive spatial light modulator 98 enters the pixel shift element 76, undergoes the pixel shift process as described above, and enters the projection optical system 77. The focusing of the projection lens is adjusted so that the reduced pixel image 97 formed in the vicinity of the exit side end face of the transmissive spatial light modulator 98 is just magnified on the screen.
[0117]
FIG. 29 is a diagram showing an example in which a transmissive spatial light modulator is applied to a color image projection apparatus.
In this configuration, an illumination light source for each color corresponding to each image display element is required. The transmissive spatial light modulator 98 illuminated by the three primary colors of the light sources 65R, 65G, and 65B from the three directions with respect to the color separation prism 74 modulates the light flux by the color-specific information. Light beams of three colors including pixel information reduced and separated to an integer of the pixel pitch by the reduction optical system are combined by the color separation prism 74 to form a color image and the pixel shifting element 76 via the light shielding member 69. Is incident on. The operation of the projection lens 77 is the same as that of the monochromatic projector shown in FIG.
[0118]
Even if the spatial light modulator becomes a transmissive type, the problem of not displaying the image flow at the time of pixel shifting is the same, so the arrangement of the light shielding area moving means is also related to the common components With respect to, basically, the configuration shown in the reflective spatial light modulation element can be applied.
[0119]
【The invention's effect】
According to the present invention, it is possible to prevent an image from being displayed during information update of the image display device. Further, even in an apparatus that performs pixel shifting, it is possible to prevent an image during pixel shifting from being displayed.
[Brief description of the drawings]
[Figure 1]Image display deviceIt is the schematic which shows an example.
[Figure 2]Shading the image areaIt is a schematic diagram for demonstrating.
[Fig. 3]Shading the image areaIt is a schematic diagram for demonstrating.
[Fig. 4]Shading the image areaIt is a schematic diagram for demonstrating.
[Figure 5]Another example of image area shadingIt is a figure for demonstrating.
[Fig. 6]Another example of image area shadingIt is a figure for demonstrating.
[Fig. 7]Another example of image area shading (2-stage parallel updateIf)It is a figure for demonstrating.
[Fig. 8]Another example of image area shading (2-stage parallel updateIf)It is a figure for demonstrating.
FIG. 9Other examples of shading image areasIt is a figure for demonstrating.
FIG. 10Example of Fig. 9It is a figure for demonstrating.
FIG. 11Example of Fig. 9It is a figure for demonstrating.
FIG.Other examples of shading image areasIt is a figure for demonstrating.
FIG. 13 is a diagram illustrating a state of light shielding of a pixel row accompanying movement of a light shielding mask portion.
FIG. 14Other examples of shading image areasIt is a figure for demonstrating.
FIG. 15FIG.It is a figure which shows the light-shielding state in the illumination light beam transmissive area | region by the helical light-shielding mask part.
FIG. 16 is a diagram showing a configuration of a light shielding member capable of temporarily covering the entire illumination light beam transmission region.
FIG. 17Other examples of shading image areasIt is a figure for demonstrating.
FIG. 18For explaining another example of shading of an image area.FIG.
FIG. 19Similar form of the information display device of the present inventionIt is a figure for demonstrating.
FIG. 20Other similar formsFIG.
FIG. 21Other similar formsIt is a figure for demonstrating.
FIG. 22Other similar formsFIG.
FIG. 23Other similar formsFIG.
FIG. 24Another embodiment of the information display device of the present inventionFIG.
FIG. 25Other similar formsFIG.
FIG. 26 is a diagram showing a configuration of a spatial light modulation element corresponding to pixel shift used in the present invention.
FIG. 27 is a diagram showing an example of an optical system when a transmissive spatial light modulation element is used.
FIG. 28 is a diagram showing an example in which a transmissive spatial light modulation element is applied to a monochromatic image projection apparatus.
FIG. 29 is a diagram illustrating an example in which a transmissive spatial light modulation element is applied to a color image projector.
FIG. 30 is a diagram illustrating an example of an image display device using a spatial light modulation element.
FIG. 31 is a diagram illustrating an example of pixel shifting.
FIG. 32 is a diagram showing a part of spatial light modulation elements arranged in a matrix.
Fig. 33 is a diagram showing a part of spatial light modulation elements arranged in a honeycomb shape.
FIG. 34 is a schematic diagram showing a relationship between information update timing of a pixel column and an information update period.
FIG. 35 is a diagram illustrating a state where light is shielded so that all pixels are not illuminated during a period from time T5 to T6.
36 is a diagram showing a state where a shaded area in FIG. 35 is also shielded from light.
FIG. 37 is a schematic diagram showing a relationship between the information update timing of the pixel column and the information update period, which is different from FIG.
FIG. 38 is a diagram for explaining a state where a pixel shifting area is shielded from light in FIG. 37;
FIG. 39 is a diagram illustrating a state where all pixels being updated are shielded from light.
[Explanation of symbols]
11 Spatial light modulator
12 pixels, pixel row
13 Shading area
31, 32 Prism
41 Rotating prism
42 Shading mask
50 Shading member
51 Shading mask
53 Illumination beam transmission area
80 Relay imaging lens

Claims (1)

In an information display device configured to display an image of a spatial light modulation element configured by a plurality of pixels that can be independently modulated and in which an image signal of each pixel is updated in a line-sequential manner in pixel column units or pixel row units ,
A light shielding means for shielding the pixel area in a band shape so that at least the pixel area being updated is not displayed;
The light shielding means is a light valve, and includes a light shielding area moving means for moving at least a light shielding area that shields the pixel area in the line sequential update direction according to a line sequential update timing of the pixel signal ,
In order toward the traveling direction of the luminous flux, it has an illumination optical system consisting of an illumination light source, a filter for removing unnecessary components of illumination light, and an integrator optical system,
Further, a polarizing beam splitter is arranged at the subsequent stage, a linearly polarizing plate is arranged in the light beam between the polarizing beam splitter and the illumination light source,
The illumination light linearly polarized by the linear polarizing plate is reflected by the polarization beam splitter,
Color separation into RGB components is performed by a color separation prism arranged at the subsequent stage of the polarization beam splitter,
The illumination light of each color illuminates three spatial light modulation elements arranged close to the rear stage of the color separation prism, and is modulated and reflected by the three spatial light modulation elements.
Each reflected light is synthesized by the color separation prism, passes through the polarization beam splitter, reaches a projection optical system, and the projection optical system projects and displays each pixel of the spatial light modulator.
The light valve of three, between each of said color separation prism and the three spatial light modulator, in proximity to each of the spatial light modulator, the information display apparatus characterized by being arranged.

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