JP2006268022A - Method and apparatus for displaying three-dimensional video - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional video display method and apparatus capable of displaying a uniform, clear, three-dimensional video without limitations on viewable directions. <P>SOLUTION: First optical pulses 12a to 12d are made incident on one of fluorescent spaces 11 at a prescribed repetitive cycle (interval L<SB>0</SB>). Second optical pulses 13a to 13d, into which cross-sectional information is written, are made incident on the other fluorescent space 11 at prescribed repetitive cycle (interval L<SB>0</SB>+ΔL) different from that of the first optical pulses. Consequently, at different positions within the fluorescent space 11, the first optical pulses 12a to 12d and the second optical pulses 12a to 12d overlap each other. Multi-photon absorption arises only at a location where the first optical pulse 12 and the second optical pulse 13 overlap each other, and thus induces fluorescence, thereby a three-dimensional video 14 is displayed which is comprised of these cross-sectional images 14a to 14d. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a three-dimensional image display method and apparatus for displaying a three-dimensional image in a fluorescent space using light pulses.

  In the fields of medical CT devices, CAD devices, etc., there is an increasing demand for three-dimensional displays that display a large amount of three-dimensional information at high speed.

  Many conventional 3D video display methods display a pseudo 3D image in a two-dimensional plane. For example, 3D CG (Computer Graphics) expresses a solid using shadows, gradations of color density, and the like, and is a pseudo 3D image representation on a 2D plane.

  In addition, there are things that produce stereoscopic parallax by showing different images on the left and right eyes with deflection glasses etc. using a two-dimensional display, but the viewpoint is limited, long time Problems such as fatigue due to use are listed. Furthermore, although there is a method of three-dimensional display by holography technology, there are problems such as that it takes time to produce a hologram and only a still image can be handled.

  For this reason, there is an increasing need for an apparatus that actually displays a 3D image in a 3D space. As a method for actually displaying a three-dimensional image in a three-dimensional space, there is a volume scanning method (depth sampling method). Specifically, this method includes (a) a varifocal mirror method, (b) a moving display method, and (c) a moving screen method.

  The above (a) is a method of reflecting a two-dimensional image in synchronization with the vibration of a concave mirror that vibrates back and forth. The above (b) is a method of displaying a three-dimensional image by moving or rotating a cross-sectional image of a stereoscopic image at a high speed through a light emitting diode display or the like. The above (c) is a method of making a stereoscopic view by projecting a cross-sectional view of a stereoscopic image on a moving screen.

As another system, (d) a method of displaying an image in a three-dimensional space by arranging two two-dimensional laser arrays at right angles and generating fluorescence at the intersection of laser beams. (For example, refer to Patent Document 1).
JP-A-5-224608

  However, in the techniques (a) to (c) described above, there are problems such as (a) the varifocal mirror method that can be expressed and the size of the concave mirror must be increased when viewing with a large number of people. It is done. The (b) moving display method and the (c) moving screen method have problems such as that the range in which a 3D image can be seen is limited or the resolution is different depending on the direction of movement, and the image tends to be unclear.

  Further, the technique (d) uses infrared light as laser light, and the two laser lights are gradually absorbed as they travel through the display medium, and the light intensity is attenuated. Therefore, the laser array side is bright and the opposite side is a dark image. This phenomenon becomes more prominent when the size of the display medium is increased.

  Accordingly, an object of the present invention is to provide a 3D image display method and apparatus capable of displaying a uniform and clear 3D image without limitation in the viewing direction.

  In order to achieve the above object, according to the present invention, a first step in which a first light pulse is incident on a fluorescent space from a predetermined direction, and a second light pulse in which cross-sectional information is written are opposite to the predetermined direction. And a second step of allowing the first light pulse and the second light pulse in the fluorescence space to enter the fluorescence space and to cause fluorescence to fluoresce at a position where the first light pulse and the second light pulse overlap each other. Provide a video display method.

  In order to achieve the above object, the present invention provides a first light pulse incident means for making a first light pulse enter a fluorescent space from a predetermined direction, and a second light pulse in which cross-sectional information is written. A second light pulse incident means for entering the fluorescence space from a direction opposite to the direction and causing the fluorescence to fluoresce at a position where the first light pulse and the second light pulse overlap in the fluorescence space. A three-dimensional video display device is provided.

  According to the above three-dimensional image display method and apparatus, by superimposing the first light pulse and the second light pulse in the fluorescence space, the multi-photon absorption is strongly caused only at the position where the light pulse overlaps, and the fluorescence is generated. To emit. Therefore, by controlling the incident timing of the first and second light pulses to the fluorescence space, the overlapping position of the first light pulse and the second light pulse in the fluorescence space can be changed, By making it fluoresce at the position, a three-dimensional image composed of a plurality of cross-sectional images can be displayed.

  According to the present invention, there is no restriction on the viewing direction, and a homogeneous and clear three-dimensional image can be displayed.

[Principle of the present invention]
FIG. 1 shows a configuration for explaining the basic principle of a 3D image display method according to the present invention. In FIG. 1, a first light pulse 12 and a second light pulse 13 are incident on the fluorescence space 11 from opposite sides along one optical axis penetrating the fluorescence space 11.

  The fluorescent space 11 is filled with a phosphor or a gas, liquid or solid containing the phosphor. As the phosphor, a substance exhibiting high two-photon fluorescence efficiency such as a two-photon fluorescent dye is preferable. As the dye having high two-photon fluorescence efficiency, generally known dyes such as Rhodamine dye, Fluorescein dye, DiI dye, and Coumarin dye can be used. In addition, dyes exhibiting high two-photon fluorescence efficiency described in JP-A Nos. 2004-123668, 2004-224746, 2001-520737, and 2004-29480 are also included in the present invention. Applicable. Here, when the fluorescent space 11 is made of a fluorescent material dispersed in an organic solvent, a deuterium substitution solvent transparent to the wavelengths of the first light pulse 12 and the second light pulse 13 is used as the solvent. It is preferable. Of the first optical pulse 12 and the second optical pulse 13, the longer optical pulse is considered to have a near-infrared to infrared wavelength, but a two-photon fluorescent material is dispersed in an organic solvent. In the case where the resulting fluorescent space is used as a fluorescent space, most of the organic solvent has absorption in the infrared region, so that the energy of the light pulse cannot be effectively used. Therefore, the solvent containing the phosphor is preferably a deuterated solvent.

  When the first light pulse 12 is incident from one side of the fluorescence space 11 and the second light pulse 13 is incident from the other side of the fluorescence space 11, the first light pulse 12 and the second light pulse 13 are converted into the fluorescence space 11. Overlap. At the overlapped position, the phosphor causes multiphoton absorption more strongly than where the first light pulse 12 and the second light pulse 13 do not overlap, and emits fluorescence in the process of relaxing the excited electrons. Therefore, by adjusting the shape of the position where the first light pulse 12 and the second light pulse 13 overlap, a cross-sectional image of a desired shape is displayed by fluorescence in the fluorescence space 11.

As shown in FIG. 1, the first optical pulses 12a, 12b, 12c, 12d,... Are incident on the fluorescent space 11 at a constant repetition period (interval L ₀ ), and the second optical pulses 13a, 13b, 13c,. If the light beams 13d,... Are incident on the fluorescent space 11 at a constant repetition period (interval L ₀ + 2ΔL) different from that of the first light pulse 12, the first light pulse 12 and the second light pulse 13 are incident on each other. Since the timing is different, the positions where the cross-sectional images are displayed are different. In FIG. 1, L _{1 to} L ₄ indicate the distances until the first light pulse 12 and the second light pulse 13 overlap, and ΔL indicates the interval between the cross-sectional images.

  When the first light pulse 12a and the second light pulse 13a overlap in the fluorescent space 11, a cross-sectional image 14a is displayed. Similarly, the cross-sectional image 14b is formed by the first light pulse 12b and the second light pulse 13b, the cross-sectional image 14c is formed by the first light pulse 12c and the second light pulse 13c, and the first light pulse 12d and the second light pulse 12c. The cross-sectional images 14d are respectively displayed by the light pulse 13d. As a result, one three-dimensional image 14 is displayed in the fluorescent space 11 from the four cross-sectional images 14a to 14d at the interval ΔL. Although the fluorescence timings of the cross-sectional images 14a to 14d are different, they are recognized as if they were simultaneously displayed on the human eye due to the afterimage phenomenon of the human eye, and therefore, one tertiary that combines these cross-sectional images 14a to 14f. The original image 14 is displayed.

  In order to make the shape of the cross-sectional image a desired shape, it is necessary to make the shape of the portion where the cross-sections of the two light pulses 12 and 13 overlap each other into a desired shape. Specifically, the cross-sectional shape of the first light pulse 12 is set to a shape that covers a certain range in the fluorescent space 11, and the cross-sectional shape of the second light pulse 13 is set to a desired cross-sectional shape. As a result, the cross-sectional shape of the second light pulse 13 is displayed in the fluorescent space 11. Furthermore, a desired three-dimensional image can be obtained by changing the cross-sectional shape of the second light pulse 13 in accordance with the position where the cross-sectional image is displayed.

(Principle of fluorescence generation)
Next, the principle of fluorescence generation by multiphoton absorption will be described with reference to FIGS. The three-dimensional image display method according to the present invention enables display in a three-dimensional space by superimposing two light pulses in a fluorescent space and emitting fluorescence only at the overlapping point. In order to obtain a clear three-dimensional image, a high On / Off ratio between a place where light shines and a place where light does not shine is required. In the present invention, it is possible to obtain a high On / Off ratio by selecting the wavelength of the light pulse and the multiphoton absorption energy of the phosphor. However, the On / Off ratio represents the fluorescence intensity ratio between the place where the first light pulse 12 and the second light pulse 13 overlap and the place where they do not overlap.

であることが必要であり、数式（１）、数式（２）、数式（３）を満たすとき、第１の光パルス１２と第２の光パルス１３が重なる場所で、二光子吸収が起きる。ただし、ｃは光の速度、ｈはプランク定数である。 When the wavelength of the first optical pulse 12 is λ ₁ , the optical intensity is I ₁ , the wavelength of the second optical pulse 13 is λ ₂ , the optical intensity is I _2, and the second optical pulse 13 is an optical pulse train In addition, the number of optical pulses included in the optical pulse train is N, and the excitation energy of the phosphor is Ea or more and Eb or less. At this time, in order to generate strong fluorescence only at the position where the first light pulse 12 and the second light pulse 13 overlap,

Therefore, when Expressions (1), (2), and (3) are satisfied, two-photon absorption occurs at the place where the first optical pulse 12 and the second optical pulse 13 overlap. Where c is the speed of light and h is the Planck's constant.

であるときは（図２参照）、励起エネルギーが、Ｅａ以上Ｅｂ以下における蛍光体の二光子吸収定数をβとすると、蛍光強度は吸収の大きさに比例するので、第１の光パルス１２と第２の光パルス１３が重なっている場所と重なっていない場所の蛍光強度比（Ｏｎ／Ｏｆｆ比）は、

のように表され、Ｎ＝１、Ｉ_１＝Ｉ_２で最大値２となり、Ｎが増えるほどＯｎ／Ｏｆｆ比は低くなる。 Furthermore,

2 (see FIG. 2), if the two-photon absorption constant of the phosphor with an excitation energy of Ea to Eb is β, the fluorescence intensity is proportional to the magnitude of absorption. The fluorescence intensity ratio (On / Off ratio) between the place where the second light pulse 13 overlaps and the place where it does not overlap is as follows.

The maximum value is 2 when N = 1 and I ₁ = I ₂ , and the On / Off ratio decreases as N increases.

であるときには（図３参照）、三光子吸収エネルギーがＥａ以上Ｅｂ以下における蛍光体の三光子吸収定数をγとすると、

となり、第２の光パルス１３による三光子吸収が無視できるほど小さい範囲では、

であれば、Ｏｎ／Ｏｆｆ比は大きくなる。 Also,

(See FIG. 3), when the three-photon absorption constant of the phosphor having a three-photon absorption energy of Ea to Eb is γ,

In the range where the three-photon absorption by the second light pulse 13 is so small that it can be ignored,

If so, the On / Off ratio increases.

であれば（図４参照）、Ｏｎ／Ｏｆｆ比は、

となり、β＞＞γであるから、数式（７）よりもさらに大きくなる。 further,

If so (see FIG. 4), the On / Off ratio is

Therefore, since β >> γ, it is larger than Expression (7).

もしくは（図６参照）、

であれば、光パルス同士が重なっていない場所では、ほとんど多光子吸収が起こらないため、Ｏｆｆはほぼ０となる。 Furthermore (see FIG. 5),

Or (see FIG. 6),

If so, multi-photon absorption hardly occurs in a place where the light pulses do not overlap with each other, so Off is almost zero.

  That is, in order to obtain a high On / Off ratio, it is desirable that the relationship between the phosphor and the light pulse satisfies the formulas (1), (2), (3), (6), and (8). , Formula (1), Formula (2), Formula (3), Formula (9) are more preferably satisfied, Formula (1), Formula (2), Formula (3), Formula (11), or Formula ( It is most desirable to satisfy 1), Formula (2), Formula (3), and Formula (12).

に比例する。数式（１）、数式（２）、数式（３）、数式（６）、数式（８）、もしくは数式（１）、数式（２）、数式（３）、数式（９）、を満たす以外に、蛍光体の二光子吸収係数βと光パルスの強度Ｉ_１・Ｉ_２が大きい必要がある。ただし、Φは蛍光体の量子効率を表す。 However, in order to obtain a clearer three-dimensional image, high fluorescence efficiency is required in addition to a high On / Off ratio. The fluorescence efficiency generated by the overlap of the first light pulse 12 and the second light pulse 13 is

Is proportional to In addition to satisfying formula (1), formula (2), formula (3), formula (6), formula (8), or formula (1), formula (2), formula (3), formula (9) The two-photon absorption coefficient β of the phosphor and the light pulse intensities I ₁ and I ₂ must be large. Where Φ represents the quantum efficiency of the phosphor.

  As described above, in order to display one cross-sectional image constituting the three-dimensional image 14 at a desired position in the fluorescent space 11, the incident timings of the first light pulse 12 and the second light pulse 13 are entered. Need to be adjusted. Hereinafter, the 3D image display method according to the embodiment of the present invention will be described more specifically.

[First Embodiment]
FIG. 7 shows a 3D video display method according to the first embodiment of the present invention. The apparatus applied to the 3D image display method of the first embodiment is a pulse light source (not shown) that emits the first optical pulse 12 and the second optical pulse 13 at a constant repetition period (interval L ₀ ). Then, the optical path length of the first optical pulse 12 emitted from the pulse light source is changed to generate the first optical pulse 12 having a constant repetition period (interval L ₀ + 2ΔL) and incident from one side of the fluorescent space 11 An optical path length control mechanism 15 that performs the writing, and the second light pulse 13 emitted from the pulse light source writes the cross-sectional information corresponding to the cross-sectional image signal, and enters from the other side of the fluorescence space 11. And a control unit (not shown) that controls each unit. In the figure, Ma to Md are reflection mirrors.

  The optical path length control mechanism 15 adjusts the optical path length from the pulse light source (not shown) to the fluorescent space 11 under the control of the control unit. By adjusting the optical path length, the optical path length control mechanism 15 adjusts the optical path length. The difference between the optical path lengths of the two optical pulses 12 and 13 changes, and the incident timing changes.

  Specifically, the switching mirrors 15a to 15d obtained by combining a pair of mirrors are arranged at an interval ΔL equal to the interval ΔL of the cross-sectional images 14a to 14d, and one of the switching mirrors 15a to 15d is selected and switched. The light pulses are reflected by the mirrors 15a to 15d. At this time, since the optical path lengths are different depending on the selected switching mirrors 15a to 15d, the overlapping position with the other second light pulse 13 is changed, whereby the position where the cross-sectional image is displayed in the fluorescent space 11 is changed. Different.

  In FIG. 7, four pairs of switching mirrors 15a to 15d are provided, but the number of the switching mirrors is not limited. Also, 15a, 15b, 15c, and 15d are sequentially set from the switching mirror having the longest optical path length.

  As the spatial light modulator 16, a liquid crystal spatial light modulator can be used. By controlling the voltage applied to each pixel of the liquid crystal spatial light modulator based on the cross-sectional image signal, a second light pulse 13 having a light pattern corresponding to the cross-sectional image signal is generated, and the second light pulse 13 is generated. Section information is written in Fluorescence occurs in a portion corresponding to the cross-section information at a position where the first light pulse 12 in the fluorescence space 11 and the second light pulse 13 in which the cross-section information is written, and a desired cross-sectional image is obtained. A micromirror array can also be used as the spatial light modulator.

  The change timing of the optical path length by the optical path length control mechanism 15 and the writing timing of the cross-sectional information by the spatial light modulator 16 are controlled so as to be synchronized by a control unit (not shown).

(Display operation according to the first embodiment)
When a control unit (not shown) selects the switching mirror 15a by the optical path length control mechanism 15 and emits the first light pulse 12a and the second light pulse 13a from the pulse light source (not shown) at the same timing, the first light pulse Since the optical path length of 12a is the longest, the arrival time of the first optical pulse 12a to the fluorescent space 11 is the latest, and as a result, the overlapping point of the first optical pulse 12a and the second optical pulse 13a is the fluorescent space. 11 and the cross-sectional image 14a is displayed.

  Next, when the switching mirror 15b is selected by the optical path length control mechanism 15, when the first optical pulse 12b and the second optical pulse 13b are emitted at the same timing, the first optical pulse 12b is controlled by the optical path length control. By passing through the mechanism 15, the optical path length is adjusted, and the timing to reach the fluorescent space 11 is adjusted. As a result, a cross-sectional image 14b is displayed at a point where the two light pulses 12b and 13b overlap.

  Similarly, when the switching mirror 15c or 15d is selected by the optical path length control mechanism 15, the optical path length is further shortened, so that the arrival time of the first optical pulse 12 to the fluorescence space 11 is accelerated, and the two optical pulses 12, The overlapping point 13 moves in the direction in which the second light pulse 13 is incident, and the cross-sectional image 14c and the cross-sectional image 14d are displayed. In this way, the three-dimensional image 14 including the cross-sectional images 14a to 14d is displayed.

  According to the first embodiment, since only one spatial light modulator is required, it is possible to display a clear 3D image with a simple configuration, no limitation in the viewing direction, and uniform resolution and brightness. it can.

[Second Embodiment]
FIG. 8 shows a 3D video display method according to the second embodiment of the present invention. In the 3D image display method according to the second embodiment, the first optical pulses 12a, 12b, 12c,... Are incident on one side of the fluorescent space 11 at a constant repetition period (interval L ₀ ), An optical pulse train 130a, 130b, 130c,... Consisting of N second optical pulses 13a to 13f is made incident on the other side of the fluorescent space 11 at the same repetition period (interval L ₀ ) as the optical pulse, and N sectional images are obtained. A three-dimensional image 14 composed of 14a to 14f is displayed. In FIG. 8, L _{1 to} L ₃ indicate distances until the first optical pulses 12a, 12b, and 12c overlap with the first second optical pulse 13a of each of the optical pulse trains 130a, 130b, and 130c, and ΔL Indicates the interval between the cross-sectional images.

  The N pieces of second optical pulses 13 a to 13 f are incident on the other side of the fluorescence space 11 with cross-sectional information written by the spatial light modulators on N different optical axes.

(Display operation according to the second embodiment)
First light pulses 12a, 12b, 12c,... Are incident from one side of the fluorescent space 11 at a predetermined timing, and N (six in FIG. 8) second light pulses 13a to 13a from the other side of the fluorescent space 11. An optical pulse train 130a, 130b, 130c,... Formed of 13f is incident at a predetermined timing.

  As the first optical pulse 12 and the optical pulses 13a to 13f in the optical pulse train 130 overlap, the cross-sectional images 14a to 14f are displayed at the overlapping positions. The three-dimensional image 14 is displayed by one light pulse 12 and one light pulse train 130, or M light pulses 12 and M light pulse trains 130. When the three-dimensional image 14 is displayed with one light pulse 12 and one light pulse train 130, moving image display is possible by temporally changing the cross-sectional information written in each light pulse train 130.

  According to the second embodiment, a three-dimensional moving image can be displayed by rewriting the cross-sectional information for each optical pulse train. In addition, as in the first embodiment, there is no limitation on the viewing direction, and a uniform and clear three-dimensional image can be displayed.

[Third Embodiment]
FIG. 9 shows a 3D video display method according to the third embodiment of the present invention. In the 3D image display method according to the third embodiment, M first light pulses 12 are incident on one side of the fluorescent space 11 at a constant repetition period, and N (here, two) second light pulses are incident. The M light pulse trains 130 made up of the light pulses 13a to 13f are incident on the other side of the fluorescent space 11 at a predetermined timing, and a 3D image made up of N × M cross-sectional images is displayed.

(Display operation according to the third embodiment)
.. M (three in FIG. 9) first light pulses 12a, 12b, 12c,... Are incident at a predetermined timing from one side of the fluorescent space 11, and N (in FIG. M (three in FIG. 9) optical pulse trains 130a, 130b, 130c,... Composed of two second optical pulses 13 are incident at a predetermined timing.

  When the first light pulse train 130a composed of the two second light pulses 13a and 13d is incident on the fluorescence space 11 in synchronization with the timing at which the first first light pulse 12a is incident on the fluorescence space 11, Two cross-sectional images 14a and 14d are displayed at positions where the first light pulse 12a and the second light pulses 13a and 13d overlap. When the second light pulse train 130b composed of the two second light pulses 13b and 13e is incident on the fluorescence space 11 in synchronization with the timing at which the second first light pulse 12b is incident on the fluorescence space 11, Two cross-sectional images 14b and 14d are displayed at positions where the first light pulse 12b and the second light pulses 13b and 13e overlap. When the third light pulse train 130c composed of the two second light pulses 13c and 13f is incident on the fluorescence space 11 in synchronization with the timing at which the third first light pulse 12c is incident on the fluorescence space 11, Two cross-sectional images 14c and 14f are displayed at a position where the first light pulse 12c and the second light pulses 13c and 13f overlap each other. Each of the cross-sectional images 14a to 14f is displayed at different positions, and is displayed as one three-dimensional image 14 obtained by combining these cross-sectional images.

  According to the third embodiment, since only two spatial light modulators are required, a three-dimensional moving image can be displayed with a simple configuration. In addition, as in the first embodiment, there is no limitation on the viewing direction, and a uniform and clear three-dimensional image can be displayed.

[Fourth Embodiment]
FIG. 10 shows a 3D video display method according to the fourth embodiment of the present invention. In the 3D image display method according to the fourth embodiment, the first light pulse 12 and the second light pulse 13 are emitted with a predetermined distance apart. For example, the second light pulse 12 is first emitted from the fluorescent space. 11 is reflected by the dielectric mirror M provided in the fluorescent space 11 or outside the fluorescent space 1, and then the first light pulse 12 incident after the delay is opposed to the fluorescent space 11. The first and second light pulses 12 and 13 are overlapped at the position to generate fluorescence and obtain a cross-sectional image 14. A plurality of cross-sectional images 14 a, 14 b, and 14 c are obtained by causing the first light pulse 12 and the second light pulse 13 to be incident on the fluorescence space 11 with different distances and generating fluorescence at different positions in the fluorescence space 11. Display 3D images. Here, the distance between the first optical pulse 12 and the second optical pulse 13 is made different by a distance twice as large as the distance ΔL between the plurality of cross-sectional images 14a and 14b. Thereby, the cross-sectional images 14a, 14b, etc. are obtained at different positions. Note that the repetition period of the first light pulse 13 that is incident first is set longer than the time during which the first light pulse 12 that is incident late is reflected by the dielectric mirror M and reciprocates in the fluorescent space 11. .

(Display operation according to the fourth embodiment)
The first light pulses 12a, 12b, 12c,... And the second light pulses 13a, 13b, 13c,... Are spaced from the first light pulses 12a, 12b, 12c,. Incident light enters the fluorescent space 11.

  When the first first light pulse 12a and the second light pulse 13a are incident on the fluorescent space 11, the preceding second light pulse 13a is incident on the fluorescent space 11, and is transmitted therethrough to pass through the dielectric mirror M. And enter the fluorescent space 11 again. Then, the cross-sectional image 14a is displayed at the position where the first light pulse 12a and the second light pulse 13a overlap. When the second second light pulse 13b is incident on the fluorescence space 11, the preceding second light pulse 13b is reflected by the dielectric mirror M, and the first light pulse 12b and the second light pulse 13b are reflected. The cross-sectional image 14b is displayed at the overlapping position. Similarly, the cross-sectional image 14c is displayed by the third first and second light pulses 12c and 13c. Each of the cross-sectional images 14a to 14c is displayed at a different position, and is displayed as one three-dimensional image 14 obtained by combining these cross-sectional images.

  According to the fourth embodiment, this method is suitable when there is no space in one of the fluorescent spaces 14.

  Further, if the dielectric mirror M is used so as to transmit the fluorescence wavelength, observation from the dielectric mirror M side becomes possible. Further, it is possible to prevent the three-dimensional fluorescent image from appearing on the dielectric mirror M.

  Further, when the wavelengths of the first and second light pulses 12 and 13 are different and one of the light pulses causes strong two-photon absorption, the dielectric mirror M transmits the wavelength of the light pulse that causes strong two-photon absorption. Since the wavelength of the other optical pulse that does not cause strong two-photon absorption is reflected, it is possible to avoid a decrease in contrast due to reciprocation of the light pulse that strongly causes two-photon absorption inside the phosphor.

  The first light pulse 12 may be preceded by the second light pulse, and the first light pulse 12 may be reflected by the dielectric mirror M. The dielectric mirror M may be a metal mirror.

  FIG. 11 shows Example 1 of the present invention. The three-dimensional image display apparatus 1a of Example 1 corresponds to the first embodiment, and a light source 21 that emits light pulses at a constant repetition period and a light pulse emitted from the light source 21 are the first ones. A beam splitter 22 that divides the light pulse 12 into a first light pulse 12 and a second light pulse 13, and the first light pulse 12 divided by the beam splitter 22 is expanded to one of the fluorescent spaces 11 via the reflection mirrors Ma to Mc. And a pair of rotating mirrors that select the optical paths Ra to Rh of the second optical pulse 13 divided by the beam splitter 22, which are provided at the front and rear stages of the expanding optical system 26 a and the spatial light modulator 24 a described later. Units 23a and 23b, a spatial light modulator 24 for writing cross-sectional information to the second optical pulse 13 based on the cross-sectional image signal, and a delay for adjusting the optical path length of the second optical pulse 13. It includes a road 25 and the second optical pulse 13 from the rotary mirror unit 23b and the magnifying optical system 26b incident on an enlarged scale in the other fluorescent space 11, a control unit (not shown) for controlling each part of the apparatus. The details of the rotating mirror units 23a and 23b will be described later.

  As the light source 21, an optical pulse laser having a time width of 100 femtoseconds, a repetition frequency of 1 kHz, and a wavelength of 800 nm is used.

  FIG. 12 shows details of the pair of rotating mirror portions 23a and 23b. The incident-side rotating mirror unit 23a has a plurality of optical paths, and has a function as an optical path switching unit that distributes an incident optical pulse by sequentially switching the plurality of optical paths. A plurality of disk-shaped rotating mirrors 230 each having a triangular triangular mirror part 230a capable of blocking the optical axis or allowing the optical pulse 13 to pass through, and one fixed mirror 231 disposed at the rearmost part. When a plurality of rotating mirrors 230 are rotated with a predetermined phase difference and the light pulse 13 is blocked by the triangular mirror part 230a of any one of the rotating mirrors 230, the light pulse 13 is reflected by the rotating mirror 230 and desired. Change the path to the optical axis. Therefore, by controlling the timing at which the light pulse 13 passes and the rotation timing of the rotating mirror 230, it is possible to select desired optical paths Ra to Rh for the second light pulse 13.

  The rotating mirror unit 23b has the same configuration as the rotating mirror unit 28a described above, and the incident side and the reflecting side are switched. The rotating mirror unit 23b functions as an optical axis matching optical system that matches the optical axes of a plurality of incident second optical pulses, and reliably reflects the incident optical pulses toward the same optical axis. Therefore, the rotating mirror unit 23a and the rotating mirror unit 23b are configured to rotate in synchronization as shown in FIG.

  The spatial light modulator 24 includes a spatial light modulator 240, an expansion optical system 241 disposed in front of the spatial light modulator 240, and a spatial light modulator on the optical paths Ra to Rh selected by the rotating mirror unit 23a. 240, and a reduction optical system 242 arranged at the subsequent stage of 240.

  The delay optical path 25 adjusts the interval of the second optical pulse 13 by adjusting the optical path length of the second optical pulse 13 that passes through the optical paths Ra to Rh of the spatial light modulator 24. The reflection mirror 250 is disposed at an appropriate position.

  Selection of the optical paths Ra to Rh by the rotating mirror unit 23a, writing of cross-sectional information by the spatial light modulator 240, and optical axis matching operation by the rotating mirror unit 23b are controlled to be synchronized by a control unit (not shown).

The fluorescent space 11 is filled with an organic solvent in which Rhodamine dye is dissolved. This Rhodamine dye is known to be a fluorescent dye that satisfies Formulas (1), (2), and (3) with respect to λ ₁ = 800 nm and λ ₂ = 800 nm, and has high two-photon fluorescence efficiency. ing.

(Display operation according to Example 1)
The light pulse emitted from the light source 21 is divided into the first light pulse 12 and the second light pulse 12 by the beam splitter 22. The first light pulse 12 goes to the fluorescent space 11 via the reflection mirrors Ma to Mc, and the second light pulse 13 goes to the rotating mirror unit 23a.

  The second optical pulse 13 is periodically assigned to the optical paths Ra to Rh for each pulse by the rotating mirror unit 23a, and then the cross-sectional information is written in the spatial light modulator 24, and the optical path length is adjusted by the delay optical path 25. After that, it is folded back to the fluorescent space 11 by the rotating mirror part 23b.

  The first and second light pulses 12 and 13 are incident on the fluorescence space 11 from the opposite sides after the beam diameters are enlarged by the magnifying optical systems 26a and 26b, respectively, and fluoresce at the overlapping positions. To display a cross-sectional image.

  FIG. 13 shows cross-sectional information written in the second light pulse 13, and FIG. 14 shows a cross-sectional image and a three-dimensional image. The cross-section information 17a to 17h shown in FIG. 13 is written in the second optical pulse 13 distributed to the optical paths Ra to Rh, respectively. When the cross-section information 17a to 17h is written and the second light pulse 13 and the first light pulse 12 assigned to the optical paths Ra to Rh respectively overlap in the fluorescent space 11, as shown in FIG. ˜14h are displayed, and these are displayed as the three-dimensional image 14.

  According to the first embodiment, as the distributing unit that distributes the second optical pulse 13, the rotating mirror unit 23a that distributes the second optical pulse 13 by switching the optical paths Ra to Rh is used. Increases, and a high-luminance three-dimensional image can be displayed.

  FIG. 15 shows a second embodiment of the present invention. The 3D image display apparatus 1b of Example 2 corresponds to the first embodiment. In the configuration of Example 1, first and second optical pulses 12, 13 having different wavelengths as pulse light sources are used. The first and second pulse light sources 21a and 21b that respectively emit light and the fluorescent space 11 corresponding to the first and second light pulses 12 and 13 are used, and the others are the same as in the first embodiment. It is configured.

  The first pulse light source 21a uses an optical pulse laser having a time width of 100 femtoseconds, a repetition frequency of 1 kHz, and a wavelength of 800 nm, and the second pulse light source 21b has a time width of 100 femtoseconds, a repetition frequency of 1 kHz, and a wavelength of 1400 nm. An optical pulse laser is used. These two pulse light sources 21a and 21b are configured to emit light pulses in synchronization.

The fluorescent space 11 is filled with an organic solvent in which Rhodamine dye is dissolved. This Rhodamine dye is a fluorescent dye that satisfies Formula (1), Formula (2), Formula (3), and Formula (6) with respect to λ ₁ = 800 nm and λ ₂ = 1400 nm, and has high two-photon fluorescence efficiency. It is known that there is. The intensity of the 1400 nm light pulse is sufficiently higher than the intensity of the 800 nm light pulse.

(Display operation according to embodiment 2)
The first light pulse 12 having a wavelength of 800 nm emitted from the first pulse light source 21a goes to the fluorescent space 11 through the reflection mirrors Ma and Mb. On the other hand, the second light pulse 13 having a wavelength of 1400 nm emitted from the second pulse light source 21b travels to the rotating mirror unit 23a.

  The second optical pulse 13 is periodically distributed to the optical paths Ra to Rh for each pulse by the rotating mirror unit 23a, and then the cross-sectional information is written in the spatial light modulation unit 24, and the optical path length is adjusted by the delay optical path 25. After that, it is folded back to the fluorescent space 11 by the rotating mirror part 23b.

  The first and second light pulses 12 and 13 are incident on the fluorescence space 11 from the opposite sides after the beam diameters are enlarged by the magnifying optical systems 26a and 26b, respectively, and fluoresce at the overlapping positions. To display a cross-sectional image. As described above, the optical pulses 12 and 13 having the wavelength of 1400 nm and the wavelength of 800 nm are overlapped on the same axis in the fluorescent space 11, so that a cross-sectional image is displayed with a high On / Off ratio. As in the first embodiment, the fluorescent space 11 displays cross-sectional images 14a to 14h as shown in FIG.

  According to the second embodiment, the first and second light pulses 12 and 13 having different wavelengths are used, and similarly to the first embodiment, the rotating mirror portion 23a having a high light use efficiency is used. Therefore, the contrast is high. High brightness and clear 3D images can be displayed.

  FIG. 16 shows a third embodiment of the present invention. The three-dimensional image display device 1c of Example 3 corresponds to the first embodiment, is based on optical pulse excitation with a different wavelength, and includes a pulse light source 21 that emits an optical pulse at a constant repetition period, and a pulse A beam splitter 22 that divides the light pulse emitted from the light source 21 into a first light pulse 12 and a second light pulse 13, an optical path length control mechanism 27 that changes the optical path length of the first light pulse 12, A wavelength converter 28 that changes the wavelength of the second optical pulse 13, a spatial light modulation unit 24 that writes cross-sectional information corresponding to the cross-sectional image signal to the second optical pulse 13, and the first and second optical pulses 13 Are provided with a pair of magnifying optical systems 26a and 26b that enter the fluorescent space 11 with their beam diameters enlarged, and a control unit (not shown) that controls each part of the apparatus. In FIG. 16, Ma to Mg are reflection mirrors.

  As the pulse light source 21, an optical pulse laser having a time width of 100 femtoseconds, a repetition frequency of 1 kHz, and a wavelength of 800 nm is used.

  The wavelength converter 28 converts the wavelength 800 nm of the second optical pulse 13 divided by the beam splitter 22 to a wavelength of 1400 nm.

  The optical path length control mechanism 27 is configured in the same manner as the optical path length control mechanism 15 shown in FIG. 7, and includes eight switching mirrors 27a to 27h in which a pair of mirrors are combined.

The fluorescent space 11 is filled with an organic solvent in which Rhodamine dye is dissolved. This Rhodamine dye is a fluorescent dye that satisfies Formula (1), Formula (2), Formula (3), and Formula (6) with respect to λ ₁ = 800 nm and λ ₂ = 1400 nm, and has high two-photon fluorescence efficiency. It is known that there is. The intensity of the 1400 nm light pulse is sufficiently higher than the intensity of the 800 nm light pulse.

(Display operation according to Example 3)
An optical pulse having a wavelength of 800 nm emitted from the pulse light source 21 is divided into a first optical pulse 12 and a second optical pulse 13 by a beam splitter 22. The first light pulse 12 enters the optical path length control mechanism 27 via the reflection mirrors Ma to Mc, and after the optical path length is periodically switched by the optical path length control mechanism 27, the first optical pulse 12 passes through the reflection mirrors Md and Me. To the fluorescent space 11.

  On the other hand, the other second optical pulse 13 divided by the beam splitter 22 is converted from a wavelength of 800 nm to 1400 nm by the wavelength converter 28 and then incident on the spatial light modulator 24 via the reflection mirror Mf. Then, the cross-section information is written in the spatial light modulator 24. At this time, since the optical path length control mechanism 27 and the spatial light modulation unit 24 are controlled to synchronize with each other, the optical path length of the first optical pulse 12 is adjusted by the optical path length control mechanism 27 so that the two light beams The position where the pulses overlap is adjusted to a desired position, and information on the cross-sectional image to be displayed at that position is written in the second light pulse 13 in the spatial light modulator 24. The second light pulse 13 from the spatial light modulator 24 enters the magnifying optical system 26b via the reflection mirror Mg.

  The first and second light pulses 12 and 13 are enlarged in their beam diameters by the magnifying optical systems 26a and 26b, respectively, and then enter the fluorescence space 11 from opposite sides, and fluoresce at the overlapping positions. The cross-sectional images 14a to 14h are displayed. As described above, the light pulses of 1400 nm and 800 nm are coaxially opposed and overlapped in the fluorescent space 11 so that a cross-sectional image is displayed with a high On / Off ratio. As in the other embodiments, the fluorescence space 11 displays cross-sectional images 14 a to 14 h as shown in FIG. 14, and these are displayed as a three-dimensional image 14.

  According to the third embodiment, since the first and second optical pulses 12 and 13 having different wavelengths are used, it is possible to display a three-dimensional image with high contrast. Further, since only one spatial light modulator is required, the configuration can be simplified.

  FIG. 17 shows a fourth embodiment of the present invention. The three-dimensional image display apparatus 1d of Example 4 corresponds to the second embodiment, is based on optical pulse excitation with different wavelengths, and a pulse light source 21 that emits light pulses at a constant repetition period, and a pulse light source A beam splitter 22 that divides the light pulse emitted from 21 into a first light pulse 12 and a second light pulse 13, an SHG crystal 29 that converts the wavelength of the first light pulse 12, a filter 30, A split optical system 31 that divides the second light pulse 13 into a plurality of second light pulses 13 corresponding to the number of cross-sectional images, and spatial light that writes cross-sectional information corresponding to the cross-sectional image signal to the second light pulse 13 A modulation unit 24; a delay optical path 25 that adjusts the optical path length of the second optical pulse 13; an optical axis matching optical system 32 that matches the optical axes of the plurality of second optical pulses 13; Enlarged light pulses 12 and 13 Comprising Te and a pair of enlarging optical system 26,26b entering the fluorescent space 11, and a control unit (not shown) for controlling the respective units of the apparatus.

  As the pulse light source 21, an optical pulse laser having a time width of 100 femtoseconds, a repetition frequency of 1 kHz, and a wavelength of 800 nm is used.

  The SHG crystal 29 is for converting the wavelength of the first optical pulse 12 from 800 nm to 400 nm, and the filter 30 blocks light of different wavelengths, and only the first optical pulse 12 having a wavelength of 400 nm is used. Let it pass.

The fluorescent space 11 is filled with a phosphor that satisfies Formula (1), Formula (2), Formula (3), and Formula (6) for λ ₁ = 400 nm and λ ₂ = 800 nm.

  The splitting optical system 31 splits the second light pulse 13 into a plurality of second light pulses 13 corresponding to the number of cross-sectional images 14a to 14h using a plurality of beam splitters 310 and a plurality of reflection mirrors 311. Is.

  The optical axis matching optical system 32 uses a plurality of beam splitters 320 and a plurality of reflection mirrors 321 to match the plurality of second optical pulses 13 on the same optical axis.

(Display operation according to embodiment 4)
The light pulse emitted from the light source 21 is divided into the first light pulse 12 and the second light pulse 13 by the beam splitter 22. The first light pulse 12 is wavelength-converted from 800 nm to 400 nm by the SHG crystal 29, passes through the filter 30, and travels toward the fluorescence space 11.

  Further, the second optical pulse 13 is divided into a plurality of optical paths (eight in FIG. 11) by the dividing optical system 31, and then the cross-sectional information is written in each optical pulse 13 by the spatial light modulator 24.

  Thereafter, the incident timing of each second optical pulse 13 is adjusted by the optical path length by passing through the delay optical path 25, and is again superimposed on one optical axis by the optical axis matching optical system 32. At this time, since the optical path lengths through which the optical pulses 13 have passed are different, they do not overlap each other, and as a result, one optical pulse train is obtained.

  The optical pulse train composed of the plurality of second optical pulses 13 obtained in this way is enlarged in beam diameter by the magnifying optical system 26b, and then enters one of the fluorescent spaces 11, and the first optical pulse 12 also has its beam diameter enlarged by the magnifying optical system 26 a and then enters the other of the fluorescent space 11. The first optical pulse 12 and the optical pulse train made up of the plurality of second optical pulses 13 that are incident from opposite directions overlap each other, and the respective cross-sectional images 14 a to 14 h are displayed in the fluorescent space 11. As in the other embodiments, cross-sectional images 14 a to 14 h are displayed in the fluorescent space 11, and these are displayed as the three-dimensional image 14.

  According to the fourth embodiment, since the first and second optical pulses 12 and 13 having different wavelengths are used, it is possible to display a three-dimensional image with high contrast. In addition, a three-dimensional moving image can be displayed by rewriting the cross-sectional information for each optical pulse train.

  FIG. 18 shows a fifth embodiment of the present invention. The 3D image display apparatus 1d of Example 5 corresponds to the fourth embodiment, and the first light pulse 12 and the second light pulse 13 are emitted with a predetermined distance therebetween, and either one of the lights is emitted. After the pulse is first incident and reflected by the dielectric mirror M, it is overlapped with the light pulse incident later, thereby generating fluorescence and obtaining a cross-sectional image.

  This 3D image display device 1d divides a light source 21 that emits light pulses at a constant repetition period, and a light pulse emitted from the pulse light source 21 into a first light pulse 12 and a second light pulse 13. A beam splitter 22, an optical path length control mechanism 27 that changes the optical path length of the first optical pulse 12, a wavelength converter 28 that changes the wavelength of the second optical pulse 13, and a cross section of the second optical pulse 13. Of the combined optical pulses, the spatial light modulator 24 for writing cross-sectional information corresponding to the image signal, the expanding optical system 26a that combines the first and second optical pulses 13 and enters the fluorescent space 11, and the combined optical pulses A dielectric mirror M that reflects the preceding light pulse and a control unit (not shown) that controls each unit of the apparatus are provided. In FIG. 18, Ma to Mh are reflection mirrors.

  As the dielectric mirror M, for example, a dielectric mirror that reflects light having a wavelength of 1400 nm and transmits light having a wavelength of 800 nm is used.

  As the pulse light source 21, an optical pulse laser having a time width of 100 femtoseconds, a repetition frequency of 1 kHz, and a wavelength of 800 nm is used.

  The wavelength converter 28 converts the wavelength 800 nm of the second optical pulse 13 divided by the beam splitter 22 to a wavelength of 1400 nm.

  The optical path length control mechanism 27 is configured in the same manner as the optical path length control mechanism 15 shown in FIG. 7, and includes eight switching mirrors 27a to 27h in which a pair of mirrors are combined.

The fluorescent space 11 is filled with an organic solvent in which Rhodamine dye is dissolved. This Rhodamine dye is a fluorescent dye that satisfies Formula (1), Formula (2), Formula (3), and Formula (6) with respect to λ ₁ = 800 nm and λ ₂ = 1400 nm, and has high two-photon fluorescence efficiency. It is known that there is. The intensity of the 1400 nm light pulse is sufficiently higher than the intensity of the 800 nm light pulse.

(Display operation according to embodiment 5)
An optical pulse having a wavelength of 800 nm emitted from the pulse light source 21 is divided into a first optical pulse 12 and a second optical pulse 13 by a beam splitter 22. The first light pulse 12 enters the optical path length control mechanism 27 via the reflection mirrors Ma to Mc, and after the optical path length is periodically switched by the optical path length control mechanism 27, the reflection mirrors Md, Mh, Me To the fluorescent space 11.

  On the other hand, the other second optical pulse 13 divided by the beam splitter 22 is converted from a wavelength of 800 nm to 1400 nm by the wavelength converter 28 and then incident on the spatial light modulator 24 via the reflection mirror Mf. Then, the cross-section information is written in the spatial light modulator 24. At this time, since the optical path length control mechanism 27 and the spatial light modulation unit 24 are controlled to synchronize with each other, the optical path length of the first optical pulse 12 is adjusted by the optical path length control mechanism 27 so that the two light beams The position where the pulses overlap is adjusted to a desired position, and information on the cross-sectional image to be displayed at that position is written in the second light pulse 13 in the spatial light modulator 24. The second light pulse 13 from the spatial light modulator 24 is incident at a predetermined distance from the first light pulse 12 via the reflection mirror Mh, and is incident on the magnifying optical system 26b.

  The first and second light pulses 12 and 13 are enlarged in beam diameter by the magnifying optical system 26a, respectively, and then enter the fluorescent space 11 from the same side at a predetermined distance, and the preceding second The light pulse 13 is reflected by the reflection mirror M, emits fluorescence at the position where the reflected light and the first light pulse 12 overlap, and displays the cross-sectional images 14a to 14c. As described above, the light pulses of 1400 nm and 800 nm are coaxially opposed and overlapped in the fluorescent space 11 so that a cross-sectional image is displayed with a high On / Off ratio. As in the other embodiments, the fluorescence space 11 displays cross-sectional images 14 a to 14 c as shown in FIG. 18, and these are displayed as a three-dimensional image 14.

  According to the fifth embodiment, since the first and second optical pulses 12 and 13 having different wavelengths are used, it is possible to display a three-dimensional image with high contrast. In addition, since only one magnifying optical system is required, the configuration can be simplified.

  The present invention is not limited to the above embodiments and the above examples, and various modifications can be made without departing from the scope of the invention. For example, any combination of the constituent elements of each embodiment and each example is possible without departing from the scope of the present invention. As described above, when the fluorescent space 11 is made of a fluorescent material dispersed in an organic solvent such as ethanol or acetone, it is transparent to the wavelengths of the first light pulse and the second light pulse. It is preferable to use a deuterium substitution solvent as the solvent. When hydrogen is replaced with deuterium, there is no significant change in the characteristics as a solvent, and therefore the wavelength selectivity can be improved without impairing the properties as a fluorescent space. In addition to deuterium, the absorption peak shifts even when hydrogen is replaced with chlorine, fluorine, or the like, which can be used to improve wavelength selectivity.

It is a figure which shows the principle of the three-dimensional video display method in this invention. It is the 1st figure which shows the principle of the fluorescence generation by multiphoton absorption. It is the 2nd figure which shows the principle of the fluorescence generation by multiphoton absorption. It is the 3rd figure which shows the principle of the fluorescence generation by multiphoton absorption. It is the 4th figure which shows the principle of the fluorescence generation by multiphoton absorption. It is the 5th figure which shows the principle of the fluorescence generation by multiphoton absorption. It is a figure which shows the three-dimensional video display method which concerns on the 1st Embodiment of this invention. It is a figure which shows the three-dimensional video display method which concerns on the 2nd Embodiment of this invention. It is a figure which shows the three-dimensional video display method which concerns on the 3rd Embodiment of this invention. It is a figure which shows the three-dimensional video display apparatus which concerns on the 4th Embodiment of this invention. It is a figure which shows the three-dimensional video display apparatus which concerns on Example 1 of this invention. It is a figure which shows the rotary mirror part which concerns on Example 1 of this invention. It is an example of the cross-sectional information written in each light pulse. It is an example of the three-dimensional image displayed on fluorescence space. It is a figure which shows the three-dimensional video display apparatus which concerns on Example 2 of this invention. It is a figure which shows the three-dimensional video display apparatus which concerns on Example 3 of this invention. It is a figure which shows the three-dimensional video display apparatus which concerns on Example 4 of this invention. It is a figure which shows the three-dimensional video display apparatus which concerns on Example 5 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a-1d 3D image display apparatus 11 Fluorescent space 12, 12a-12d 1st light pulse 13, 13a-13f 2nd light pulse 14 3D image 14a-14h Cross-sectional image 15 Optical path length control mechanism 15a-15d Switching mirror 16 Spatial light modulators 17a to 17h Cross-section information 21 Pulse light source 21a First pulse light source 21b Second pulse light source 22 Beam splitter 23a, 23b Rotating mirror unit 24 Spatial light modulation unit 25 Delay optical path 26a, 26b Expanding optical system 27 Optical path Length control mechanisms 27a to 27h Switching mirror 28 Wavelength converter 29 SHG crystal 30 Filter 31 Split optical system 32 Optical axis coincidence optical system 130a to 130c Optical pulse train 230 Rotating mirror 230a Triangular mirror section 231 Fixed mirror 240 Spatial light modulator 241 Magnifying optics System 242 reduction optical system 250 reflection mirror 310 B Splitter 311, reflection mirror 320, beam splitter 321, reflection mirror M, dielectric mirrors Ma to Mg, reflection mirrors Ra to Rh, optical path

Claims (27)

A first step in which a first light pulse is incident on the fluorescent space from a predetermined direction;
The second light pulse in which the cross-sectional information is written is incident on the fluorescence space from the direction opposite to the predetermined direction, and the first light pulse and the second light pulse in the fluorescence space overlap each other. A 3D image display method comprising: a second step of causing fluorescence at a position.   The first and second steps are characterized in that the first and second light pulses are caused to fluoresce at a plurality of the positions in the fluorescence space by controlling the incident timing of the first and second light pulses into the fluorescence space. The 3D image display method according to claim 1. In the first step, a plurality of the first light pulses are incident on the fluorescent space at a predetermined repetition period,
The second step is characterized in that a plurality of the second light pulses are incident on the fluorescence space at a repetition period different from the predetermined repetition period and are made to fluoresce at a plurality of the positions in the fluorescence space. The 3D image display method according to claim 1.   In the second step, a plurality of second light pulses are incident on the fluorescence space at a predetermined repetition period with respect to one first light pulse, and fluorescence is emitted at a plurality of positions in the fluorescence space. The 3D image display method according to claim 1, wherein: In the first step, a plurality of the first light pulses are incident on the fluorescent space at a predetermined repetition period,
In the second step, a plurality of pulse trains made up of N second light pulses are incident on the fluorescence space at the same repetition period as the predetermined repetition period, and the N positions in the fluorescence space are entered. The three-dimensional image display method according to claim 1, wherein the three-dimensional image display method is made to cause fluorescence. In the first step, M first light pulses are incident on the fluorescent space at a predetermined repetition period,
In the second step, M pulse trains composed of the N second light pulses are incident on the fluorescence space at the same repetition period as the predetermined repetition period, and N × M in the fluorescence space. The three-dimensional image display method according to claim 1, wherein fluorescence is emitted at said position.   The three-dimensional image display method according to claim 1, wherein different wavelengths are used for the first and second light pulses incident on the fluorescent space.   2. The 3D image display method according to claim 1, wherein the writing of the cross-sectional information to the second light pulse is performed by spatial light modulation.   In the first or second step, the preceding light pulse of the first or second light pulse is reflected to cause the first and second light pulses to enter the fluorescence space from opposite directions. The three-dimensional image display method according to claim 1, wherein: First light pulse incident means for making the first light pulse enter the fluorescent space from a predetermined direction;
The second light pulse in which the cross-sectional information is written is incident on the fluorescence space from the direction opposite to the predetermined direction, and the first light pulse and the second light pulse in the fluorescence space overlap each other. A three-dimensional image display device comprising: second light pulse incident means for causing fluorescence at a position. The first and second light pulse incident means include one light pulse light source that emits a light pulse;
The optical pulse emitted from the optical pulse light source is divided into two optical pulses, one of the two optical pulses is used as the first optical pulse, and the other optical pulse is written in the cross-sectional information. The three-dimensional image display apparatus according to claim 10, further comprising: a splitting optical system configured as a second optical pulse. The first light pulse incident means includes a first light pulse light source that emits the first light pulse,
The three-dimensional image display apparatus according to claim 10, wherein the second light pulse incident means includes a second light pulse light source that emits a second light pulse in which the cross-sectional information is written.   The said 2nd optical pulse incident means was equipped with the spatial light modulator which writes the said cross-section information into an optical pulse according to a cross-sectional image signal, and produces | generates the said 2nd optical pulse. The three-dimensional image display device described.   The three-dimensional image display apparatus according to claim 13, wherein the spatial light modulator is a liquid crystal spatial light modulator.   The second light pulse incident means has a plurality of optical paths having different optical path lengths, is provided in the plurality of optical paths, and is provided in the plurality of optical paths, and is provided in the plurality of optical paths. A plurality of spatial light modulators for writing cross-section information into a plurality of optical pulses distributed to the plurality of second light pulses by aligning optical axes of the plurality of second optical pulses in which the cross-section information is written. The three-dimensional image display apparatus according to claim 10, further comprising an optical axis matching optical system that makes a pulse incident on the fluorescent space.   The three-dimensional image display apparatus according to claim 15, wherein the distribution unit is an optical path switching unit that sequentially distributes the incident optical pulse by switching the plurality of optical paths.   The three-dimensional image display device according to claim 15, wherein the distribution unit is a divided optical system that divides an incident light pulse into a plurality of light pulses and distributes the light pulses to the plurality of optical paths.   11. The optical path length control unit configured to control the optical path length of the first optical pulse to generate a plurality of first optical pulses. 3D image display device.   11. The three-dimensional image display device according to claim 10, wherein the first or second light pulse incident means includes a wavelength converter that converts a wavelength of the light pulse.   11. The first and second light pulse incident means include a pair of magnifying optical systems that enlarge the apertures of the first and second light pulses and enter the fluorescent space. 3D image display device described in 1.   The three-dimensional structure according to claim 10, wherein the fluorescent space is made of a fluorescent material or a gas, a liquid, or a solid containing the fluorescent material, which is transparent with respect to the wavelengths of the first and second light pulses. Video display device.   The said fluorescent space is made of a deuterium-substituted organic solvent that contains a phosphor and is transparent to the wavelengths of the first light pulse and the second light pulse. 3D image display device.   The three-dimensional image display apparatus according to claim 10, wherein the fluorescent space causes the strongest multiphoton absorption at the position where the first light pulse and the second light pulse overlap each other.   11. The three-dimensional image display apparatus according to claim 10, wherein the first and second light pulse incidence units cause the first and second light pulses having different wavelengths to enter the fluorescent space.   The fluorescence space has the strongest multiphoton absorption at the position where the first light pulse and the second light pulse overlap each other by overlapping two or more of the first and second light pulses having different wavelengths. 24. The three-dimensional image display apparatus according to claim 23, wherein The first and second light pulse incident means have a light intensity of a light pulse having a shorter wavelength among the first and second light pulses having different wavelengths, which is lower than a light pulse having a longer wavelength,
The fluorescence space is transparent to the first and second light pulses, and the excitation energy to the two-photon absorption level of the fluorescence space is greater than the energy of two photons of the light pulse having the longer wavelength. 24. The three-dimensional image display device according to claim 23, wherein the three-dimensional image display device is larger and equal to or smaller than the energy obtained by adding one photon of the light pulse having a shorter wavelength.   The first or second light pulse incident means reflects the preceding light pulse of the first or second light pulse, and causes the first and second light pulses to pass through the fluorescent space from opposite directions. The three-dimensional image display apparatus according to claim 10, further comprising a mirror that is incident on the three-dimensional image.

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