JP3972945B2 - Projection type image display apparatus and transmission type screen used therefor - Google Patents

Description

  The present invention relates to a projection image display device such as a rear projection television, in which an original image displayed on a video display surface of a video generation source is enlarged by a projection lens device and projected onto a screen. More particularly, the present invention relates to a screen configuration that reduces moiré appearing on the screen when the image generation source includes a light valve having an array of fixed pixels.

  A rear projection television that enlarges an image displayed on a small image source such as a projection cathode ray tube using a projection lens device and projects it onto a transmissive screen can enjoy the powerful presence of a large screen image. In recent years, it has become popular for household use and business use.

  Under these circumstances, in recent years, along with a significant improvement in the definition and aperture ratio of liquid crystal panels, practical application of projection-type image display apparatuses using liquid crystal panels as image generation sources has begun.

  2. Description of the Related Art Conventionally, projection image display devices using a projection cathode ray tube as an image generation source have used a transmissive screen having a Fresnel lens sheet and a lenticular lens sheet as constituent elements. In the projection type image display apparatus having such a configuration, concentric bright and dark stripes appear on the screen due to light scattering (or reflection and refraction) on the non-lens surface of the Fresnel lens of the Fresnel lens sheet, and lenticular. It is known that parallel bright and dark fringes appear due to the light focusing action of the lenticular lens of the lens sheet, and moire occurs due to interference of these bright and dark fringes.

As a method for suppressing a level that does not stand out strength of the moire, the lens pitch of the Fresnel lens sheet (hereinafter, Fresnel referred lens pitch) lens pitch of the lenticular lens sheet with respect to P _F (hereinafter referred to as lenticular lens pitch) ratio of P _L P _L / P _{F is set} to a range of (n + 0.36) to (n + 0.43) or 1 / (n + 0.36) to 1 / (n + 0.43) (where n is 12 or less) Natural number) method (Japanese Patent Laid-Open Nos. 57-191627 and 59-95525), and the ratio P _F / P _L is in the range of 0.1505 to 0.1545, or 0.176 to 0.181. A method for setting the range (Japanese Patent Laid-Open No. 3-149540) is disclosed.

  On the other hand, various types of projection-type image display devices using a light valve type image generation source having an array of fixed pixels such as a transmissive or reflective liquid crystal panel or a micromirror array have been developed recently. When such a transmission type screen is used in these projection type image display devices, the above moire (hereinafter referred to as the first moire) due to interference between concentric bright and dark stripes by a Fresnel lens and parallel bright and dark stripes by a lenticular lens. Even if the image is not conspicuous, a new moire (hereinafter referred to as “moire”) is generated due to interference between the first moire pattern and the fine parallel stripes resulting from the arrangement of fixed pixels of the image generation source enlarged and projected on the transmission screen. The second moire) occurs, and it becomes a problem to reduce the second moire.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a projection type image display apparatus that makes both the first moire and the second moire less noticeable and obtains a good image. It is said.

As a ratio of the lenticular lens pitch P _L and the Fresnel lens pitch P _F , it has been disclosed in the prior art that the ratio as described above is preferable. However, the inventor of the present application conducted a study by sensory evaluation prior to making the present invention. The following ratio r was generally preferable in the order of (1), (2), and (3). Where, r is assumed to represent the ratio P _L / P _F or the ratio P _F / P _L, n is a natural number.

(1)

(Equation 25)
n + 0.35 <r <n + 0.45 (Equation 25)
Or

(Equation 26)
n + 0.55 <r <n + 0.65 (Equation 26)
(2)

(Equation 27)
n + 0.25 <r <n + 0.32 (Equation 27)
Or

(Equation 28)
n + 0.68 <r <n + 0.75 (Equation 28)
(3)

(Equation 29)
n + 0.05 <r <n + 0.25 (Equation 29)
Or

(Equation 30)
n + 0.75 <r <n + 0.95 (Equation 30)
According to these ratios, the intensity of moire caused by interference is at a weak level, and the moire pattern is hardly noticeable under normal viewing conditions.

  In general, the moire intensity of two types of periodic structures is such that the fractional ratio of the pitches of these periodic structures is 0, 0.5 (ie 1/2), 0.333 (ie 1/3). Empirically, the moiré intensity for values that are very simple integer ratios such as 0.667 (ie 2/3), 0.25 (ie 1/4), 0.75 (ie 3/4) Is generally known, and the ratio of the above formulas 25 to 30 is in a range that avoids the vicinity of these values. Therefore, the ratio of r described above is not limited to the combination of a Fresnel lens and a lenticular lens, and is widely effective for various types of moire.

  In view of this, in order to solve the above-mentioned problems of the prior art, the projection type image display apparatus of the present invention uses the following means.

That is, when the pitch of the pixels enlarged and projected on the screen is P _P , the Fresnel lens pitch P _F and the lenticular lens pitch P _L are expressed by the following group of first conditional expressions (Expression 1 to Expression 12). One of the inequalities and one of the second group of conditional expressions (Equation 13 to Equation 24) are set to values that satisfy simultaneously.

However, in each inequality, n represents an arbitrary natural number. Further, the following group of the first conditional expression and the group of the second conditional expression are classified into three ranks of rank 1, rank 2, and rank 3, respectively, which will be described later.
≪First conditional expression≫
<Rank 1>

(Equation 1)
n + 0.35 <P _P · | P _L −P _F | / (P _L · P _F ) <n + 0.45
...... (Equation 1)

(Equation 2)
_{n + 0.55 <P P · |} P L -P F | / (P L · P F) <n + 0.65
...... (Equation 2)

(Equation 3)
1 / (n + 0.45) <P _P · | P _L −P _F | / (P _L · P _F ) <1 / (n + 0.35)
(Equation 3)

(Equation 4)
1 / (n + 0.65) <P _P · | P _L −P _F | / (P _L · P _F ) <1 / (n + 0.55)
(Equation 4)
<Rank 2>

(Equation 5)
n + 0.25 <P _P · | P _L −P _F | / (P _L · P _F ) <n + 0.32
...... (Equation 5)

(Equation 6)
n + 0.68 <P _P · | P _L −P _F | / (P _L · P _F ) <n + 0.75
(Equation 6)

(Equation 7)
1 / (n + 0.32) <P _P · | P _L −P _F | / (P _L · P _F ) <1 / (n + 0.25)
(Equation 7)

(Equation 8)
1 / (n + 0.75) < P P · | P L -P F | / (P L · P F) <1 / (n + 0.68)
(Equation 8)
<Rank 3>

(Equation 9)
n + 0.05 <P _P · | P _L −P _F | / (P _L · P _F ) <n + 0.25
(Equation 9)

(Equation 10)
n + 0.75 <P _P · | P _L −P _F | / (P _L · P _F ) <n + 0.95
...... (Equation 10)

(Equation 11)
1 / (n + 0.25) <P _P · | P _L −P _F | / (P _L · P _F ) <1 / (n + 0.05)
(Equation 11)

(Equation 12)
1 / (n + 0.95) <P _P · | P _L −P _F | / (P _L · P _F ) <1 / (n + 0.75)
(Equation 12)
≪Second conditional expression≫
<Rank 1>

(Equation 13)
_{n + 0.35 <P L / P} F <n + 0.45 ...... ( number 13)

(Equation 14)
_{n + 0.55 <P L / P} F <n + 0.65 ...... ( number 14)

(Equation 15)
1 / (n + 0.45) < P L / P F <1 / (n + 0.35) ...... ( number 15)

(Equation 16)
1 / (n + 0.65) < P L / P F <1 / (n + 0.55) ...... ( number 16)
<Rank 2>

(Equation 17)
_{n + 0.25 <P L / P} F <n + 0.32 ...... ( number 17)

(Equation 18)
_{n + 0.68 <P L / P} F <n + 0.75 ...... ( Equation 18)

(Equation 19)
1 / (n + 0.32) < P L / P F <1 / (n + 0.25) ...... ( number 19)

(Equation 20)
1 / (n + 0.75) < P L / P F <1 / (n + 0.68) ...... ( number 20)
<Rank 3>

(Equation 21)
_{n + 0.05 <P L / P} F <n + 0.25 ...... ( number 21)

(Equation 22)
_{n + 0.75 <P L / P} F <n + 0.95 ...... ( number 22)

(Equation 23)
1 / (n + 0.25) < P L / P F <1 / (n + 0.05) ...... ( number 23)

(Equation 24)
1 / (n + 0.95) < P L / P F <1 / (n + 0.75) ...... ( number 24)

  According to the projection type image display apparatus of the present invention, the first moiré caused by the interference between the concentric bright and dark stripes by the Fresnel lens and the parallel bright and dark stripes by the lenticular lens, and the first moiré pattern and the enlarged projection on the screen are projected. In addition, both the second moire due to the interference with the fine parallel stripes resulting from the arrangement of the fixed pixels can be made inconspicuous, and an excellent image can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings.

1, in order to solve the above problems, is an explanatory diagram showing an example of the range of the lenticular lens pitch P _L and the Fresnel lens pitch P _F.

The calculation conditions in FIG. 1 are that the screen size is 50 inches diagonal (1270 mm), the screen aspect ratio (horizontal / vertical ratio) is 4: 3, the number of pixels is 800 pixels wide, 600 pixels high, and the pixel arrangement is not staggered. It is assumed that it is a lattice arrangement. Under this condition, the pixel pitch P _P enlarged and projected on the screen is P _P = 1.27 mm. However, in FIG. 1, for easy understanding, only the case where P _L > P _F and the pixel pitch P _P is P _P > P _L · P _F / (P _L −P _F ) is shown.

In Figure 1, curve MP1A-1, MP1A-2, when the P _L takes a value in the range of 0.5mm from 0 mm, the value of P _F obtained as the n = 1 in the number 1 of the upper limit, respectively Indicates the value and lower limit. Curve MP1B-1, MP1B-2 is the value of P _F obtained as the n = 1 in equation 2 above, respectively upper limit, the lower limit. Further, the curve MP2A-1 or lower is similarly obtained as n = 2, 3, 4, 5, 6 in the first and second formulas.

On the other hand, in FIG. 1, curve FL1A-1, FL1A-2, when the P _L takes a value in the range of 0.5mm from 0 mm, the value of P _F obtained as the n = 1 in Expression 13 above, The upper and lower limits are shown respectively. Curve FL1B-1, FL1B-2 is the value of P _F obtained as the n = 1 in Equation 14 above, respectively upper limit, the lower limit. Furthermore, the curve FL2A-1 and below are also obtained in the same manner as in Equations (13) and (14) where n = 2 and 3.

  FIG. 2 is an enlarged view of a part of FIG.

In FIG. 2, the region surrounded by the curves MP3A-1, MP3A-2, FL1A-1, and FL1A-2 is expressed by Equation 1 as one inequality in the group of the first conditional expressions described above, and a region that satisfies simultaneously one the number 13 and is inequality among the group of second condition, by the value of the lenticular lens pitch P _L and the Fresnel lens pitch P _F to be included in this region, The first moire due to the interference between the concentric bright and dark fringes by the Fresnel lens and the parallel bright and dark fringes by the lenticular lens is inconspicuous, and the fine parallel fringes and the first moire caused by the pixel array enlarged and projected on the screen The second moire due to interference with the pattern is also inconspicuous.

  This is due to the following actions.

The pitch P _{M in the} horizontal direction of the screen through the center of the Fresnel lens of the primary moire pattern of the first moire due to the interference between the concentric bright and dark stripes by the Fresnel lens and the parallel bright and dark stripes by the lenticular lens is the difference in the spatial frequency of each. From Equation 31 to Equation 32.

(Equation 31)
1 / P _M = | (1 / P _F ) − (1 / P _L ) | (Equation 31)

(Expression 32)
P _M = P _L · P _F / | P _L −P _F | (Equation 32)
At this time, if the values of the lenticular lens pitch P _L and the Fresnel lens pitch P _F satisfy Expression 13, the first moire pattern due to the interference between the concentric bright and dark fringes by the Fresnel lens and the parallel bright and dark fringes by the lenticular lens is conspicuous. Disappear. For example, the point Q in the center of FIG. 2 is P _L = 0.1490 mm, P _F = 0.1067 mm, P _L / P _F = 1.40, and satisfies Expression 13.

On the other hand, the relationship between the pitch P _M of the first moire pattern and the pixel pitch P _P enlarged and projected on the screen is derived from Equations 1 and 32 as shown in Equation 33.

(Expression 33)
n + 0.35 <P _P / P _M <n + 0.45 (Expression 33)
This number 33 is an inequality of the same form as the above number 13. In the case of the above point Q, P _M = 0.376 mm from Eq. 32, so P _P / P _M = 3.38, and Eq. 33 is satisfied. At this time, the first moiré pattern can be made inconspicuous by Equation 13, and the interference between the first moiré pattern and fine parallel stripes resulting from the arrangement of fixed pixels enlarged and projected on the screen can be obtained. The second moire can be inconspicuous.

  In FIG. 2, the region surrounded by the curves MP3B-1, MP3B-2, FL1A-1, and FL1A-2 in addition to the above region is one inequality in the group of the first conditional expressions described above. The region that simultaneously satisfies Equation 2 and Equation 13 that is the second inequality, and the region surrounded by the curves MP4A-1, MP4A-2, FL1B-1, and FL1B-2 is the above-mentioned first region. Of the inequality of Eq. 1 and the inequality Eq. 14 of one of the groups of the second conditional expression are simultaneously satisfied, and the curves MP4B-1, MP4B-2, FL1B-1, FL1B The region surrounded by -2 is the simultaneous expression of Equation 2 which is one inequality in the group of first conditional expressions and Equation 14 which is one inequality in the group of second conditional expressions. This is a satisfactory area, both of which have the same effects as above There is an effect.

  These regions are regions based on rank 1 inequalities in the first conditional expression and rank 1 inequalities in the second conditional expression, but are not limited to rank 1 respectively. 2 and rank 3 inequalities may be used. At this time, inequality expressions having different ranks may be combined in the first conditional expression and the second conditional expression. When combining these inequalities, a greater effect can be obtained by using the rank 2 inequalities than the rank 3 inequalities, and a greater effect can be obtained by using the rank 1 inequalities than the rank 2 inequalities.

In the above description, only the case where P _L > P _F and the pixel pitch P _P is P _P > P _L · P _F / (P _L −P _F ) is described, but P _L <P _F and When the pixel pitch P _P is P _P > P _L · P _F / (P _F −P _L ), it is easily understood that P _L may be read in the above description. Further, when P _L > P _F and the pixel pitch P _P is P _P <P _L · P _F / (P _L −P _F ), and P _L <P _F and the pixel pitch P _P is P _P <P. _{In the case of L} · P _F / (P _F −P _L ), a suitable region of P _L and P _F can be theoretically derived from the same concept as in FIG. 1 or FIG. However, it has the drawback that P _L = becomes extremely narrow region interspersed linear near the P _F, easily protrude from the area in case of any manufacturing errors in the P _L and P _F, too much practical use Not suitable.

In the above description, the case where P _P = 1.27 mm is described as the pixel pitch P _P , but this is naturally a value determined by the screen size and the number of displayed pixels. As an image generation source of the projection type image display device, for example, a liquid crystal panel having a screen size diagonal of 1.3 inches, a screen aspect ratio of 4: 3, and a pixel number of 800 × 600 is used on the liquid crystal panel. The pixel pitch is 0.033 mm, and the pixel pitch on the screen is P _P = 1.27 mm when the magnification of the projection lens that magnifies and projects this onto the screen is 38.46 times. Of course, not limited to the case of P _P = 1.27 mm as the value of P _P, it is apparent that the present invention can be applied also to any value.

In general, the magnification performance of the projection lens is distorted, and the magnification is not uniform over the entire screen. In this case, however, in carrying out the present invention, concentric circles near the center of the left and right sides of the screen are concentric. to decide the P _L and P _F by focusing on the pitch of the fixed pixels on the screen in the vicinity of the portion where the first moire caused by interference with the parallel light and dark fringes due to light and dark fringes and the lenticular lens is generated, practically preferable.

Is an explanatory view showing an example of the range of the lenticular lens pitch P _L and the Fresnel lens pitch P _F according to the present invention. It is the figure which expanded a part of FIG.

Claims (8)

In a transmissive screen on which a display image of a fixed pixel format video source is enlarged and projected,
A first sheet having a Fresnel lens;
A second sheet provided with a plurality of optical elements arranged in the horizontal direction of the screen for diffusing emitted light from the first sheet in the horizontal direction of the screen,
Pixel pitch P of the image generation source projected on the transmissive screen _P And a Moire pitch P expressed by the following equation generated by the Fresnel lens and the optical element: _M Ratio P with _P / P _M Wherein the pitch between the Fresnel lens and the optical element is set so as to satisfy any one of the following numerical ranges (1) to (12):
However, in the following, n is a natural number of 1 to 6, P _L Is the pitch of the optical element, P _F Is the pitch of the Fresnel lens and P _P Is determined by the product of the pixel pitch on the video source and the magnification, P _M Is determined by the following equation for the moire pitch in the vicinity of the center near the left and right ends of the transmissive screen.
P _M = (P _L ・ P _F ) / | P _L -P _F ｜
(1) n + 0.35 to n + 0.45
(2) n + 0.55 to n + 0.65
(3) 1 / (n + 0.45) to 1 / (n + 0.35)
(4) 1 / (n + 0.65) to 1 / (n + 0.55)
(5) n + 0.25 to n + 0.32
(6) n + 0.68 to n + 0.75
(7) 1 / (n + 0.32) to 1 / (n + 0.25)
(8) 1 / (n + 0.75) to 1 / (n + 0.68)
(9) n + 0.05 to n + 0.25
(10) n + 0.75 to n + 0.95
(11) 1 / (n + 0.25) to 1 / (n + 0.05)
(12) 1 / (n + 0.95) to 1 / (n + 0.75) In a transmissive screen on which a display image of a fixed pixel format video source is enlarged and projected,
A first sheet having a Fresnel lens;
A second sheet having a plurality of optical elements arranged in the horizontal direction of the screen for diffusing the emitted light from the first sheet in the horizontal direction of the screen,
The arrangement pitch of the pixels of the image generation source enlarged and projected on the transmissive screen is P _P The pitch of the Fresnel lens formed on the first sheet is P _F , And the pitch of the optical elements formed on the second sheet is P _L The pitch of the Fresnel lens and the optical element is set so as to satisfy any one of the following conditional expression groups:
However, n is a natural number of 1-6, P _P Is determined by the product of the pixel pitch on the image source and the magnification, _L -P _F | / (P _L ・ P _F ) Is a value in the vicinity of the center near the left and right ends of the transmission screen.
(Equation 1) n + 0.35 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.45
(Equation 2) n + 0.55 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.65
(Equation 3) 1 / (n + 0.45) <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <1 / (n + 0.35)
(Equation 4) 1 / (n + 0.65) <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <1 / (n + 0.55)
(Equation 5) n + 0.25 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.32
(Equation 6) n + 0.68 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.75
(Equation 7) 1 / (n + 0.32) <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <1 / (n + 0.25)
(Equation 8) 1 / (n + 0.75) <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <1 / (n + 0.68)
(Equation 9) n + 0.05 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.25
(Expression 10) n + 0.75 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.95
(Equation 11) 1 / (n + 0.25) <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <1 / (n + 0.05)
(Equation 12) 1 / (n + 0.95) <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <1 / (n + 0.75) In a transmissive screen on which a display image of a fixed pixel format video source is enlarged and projected,
A first sheet having a Fresnel lens;
A second sheet having a plurality of optical elements arranged in the horizontal direction of the screen for diffusing the emitted light from the first sheet in the horizontal direction of the screen,
The arrangement pitch of the pixels of the image generation source enlarged and projected on the transmissive screen is P _P The pitch of the Fresnel lens formed on the first sheet is P _F , And the pitch of the optical elements formed on the second sheet is P _L The pitch of the Fresnel lens and the optical element is set so as to satisfy any one of the following conditional expression groups:
Where n is a natural number from 1 to 6 and P _L > P _F And P _P > (P _L ・ P _F ) / | P _L -P _F Satisfy the relationship | _P Is determined by the product of the pixel pitch on the image source and the magnification, _L -P _F | / (P _L ・ P _F ) Is a value near the center of the left and right ends of the transmissive screen.
(Equation 1) n + 0.35 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.45
(Equation 2) n + 0.55 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.65
(Equation 5) n + 0.25 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.32
(Expression 6) n + 0.68 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.75
(Equation 9) n + 0.05 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.25
(Expression 10) n + 0.75 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.95 In a transmissive screen on which a display image of a fixed pixel format video source is enlarged and projected,
A first sheet having a Fresnel lens;
A second sheet having a plurality of optical elements arranged in the horizontal direction of the screen for diffusing the emitted light from the first sheet in the horizontal direction of the screen,
The arrangement pitch of the pixels of the image generation source enlarged and projected on the transmissive screen is P _P The pitch of the Fresnel lens formed on the first sheet is P _F , And the pitch of the optical elements formed on the second sheet is P _L The pitch of the Fresnel lens and the optical element is set so as to satisfy any one of the following first conditional expression group and any one of the following second conditional expression group. A transmission screen;
However, n is a natural number of 1 to 6 in the following first conditional expression group, n is a natural number of 1 to 3 in the following second conditional expression group, and P _L > P _F And P _P > (P _L ・ P _F ) / | P _L -P _F Satisfy the relationship | _P Is determined by the product of the pixel pitch on the image source and the magnification, _L -P _F | / (P _L ・ P _F ) Is a value near the center of the left and right ends of the transmissive screen.
≪First conditional expression group≫
(Equation 1) n + 0.35 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.45
(Equation 2) n + 0.55 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.65
(Equation 5) n + 0.25 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.32
(Expression 6) n + 0.68 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.75
(Equation 9) n + 0.05 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.25
(Expression 10) n + 0.75 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.95
<< Second conditional expression group >>
(Equation 13) n + 0.35 <P _L / P _F <N + 0.45
(Expression 14) n + 0.55 <P _L / P _F <N + 0.65
(Expression 17) n + 0.25 <P _L / P _F <N + 0.32
(Equation 18) n + 0.68 <P _L / P _F <N + 0.75
(Expression 21) n + 0.05 <P _L / P _F <N + 0.25
(Expression 22) n + 0.75 <P _L / P _F <N + 0.95 In a transmissive screen on which a display image of a fixed pixel format video source is enlarged and projected,
A first sheet having a Fresnel lens;
A second sheet having a plurality of optical elements arranged in the horizontal direction of the screen for diffusing the emitted light from the first sheet in the horizontal direction of the screen,
The arrangement pitch of the pixels of the image generation source enlarged and projected on the transmissive screen is P _P The pitch of the Fresnel lens formed on the first sheet is P _F , And the pitch of the optical elements formed on the second sheet is P _L The pitch of the Fresnel lens and the optical element is set so as to satisfy any one of the following conditional expression groups:
Where n is a natural number from 1 to 6 and P _L <P _F And P _P > (P _L ・ P _F ) / | P _L -P _F Satisfy the relationship | _P Is determined by the product of the pixel pitch on the image source and the magnification, _L -P _F | / (P _L ・ P _F ) Is a value near the center of the left and right ends of the transmissive screen.
(Equation 1) n + 0.35 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.45
(Equation 2) n + 0.55 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.65
(Equation 5) n + 0.25 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.32
(Expression 6) n + 0.68 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.75
(Equation 9) n + 0.05 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.25
(Expression 10) n + 0.75 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.95 In a transmissive screen on which a display image of a fixed pixel format video source is enlarged and projected,
A first sheet having a Fresnel lens;
A second sheet having a plurality of optical elements arranged in the horizontal direction of the screen for diffusing the emitted light from the first sheet in the horizontal direction of the screen,
The arrangement pitch of the pixels of the image generation source enlarged and projected on the transmissive screen is P _P The pitch of the Fresnel lens formed on the first sheet is P _F , And the pitch of the optical elements formed on the second sheet is P _L The pitch of the Fresnel lens and the optical element is set so as to satisfy any one of the following first conditional expression group and any one of the following second conditional expression group. A transmission screen;
However, n is a natural number of 1 to 6 in the following first conditional expression group, n is a natural number of 1 to 3 in the following second conditional expression group, and P _L <P _F And P _P > (P _L ・ P _F ) / | P _L -P _F Satisfy the relationship | _P Is determined by the product of the pixel pitch on the image source and the magnification, _L -P _F | / (P _L ・ P _F ) Is a value near the center of the left and right ends of the transmissive screen.
≪First conditional expression group≫
(Equation 1) n + 0.35 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.45
(Equation 2) n + 0.55 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.65
(Equation 5) n + 0.25 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.32
(Expression 6) n + 0.68 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.75
(Equation 9) n + 0.05 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.25
(Expression 10) n + 0.75 <P _P ・ | P _L -P _F | / (P _L ・ P _F ) <N + 0.95
<< Second conditional expression group >>
(Equation 15) 1 / (n + 0.45) <P _L / P _F <1 / (n + 0.35)
(Equation 16) 1 / (n + 0.65) <P _L / P _F <1 / (n + 0.55)
(Equation 19) 1 / (n + 0.32) <P _L / P _F <1 / (n + 0.25)
(Equation 20) 1 / (n + 0.75) <P _L / P _F <1 / (n + 0.68)
(Equation 23) 1 / (n + 0.25) <P _L / P _F <1 / (n + 0.05)
(Equation 24) 1 / (n + 0.95) <P _L / P _F <1 / (n + 0.75) 7. The transmission screen according to claim 1, wherein the optical element is a lenticular lens. 7. The transmissive screen according to claim 1, wherein the magnification is a magnification of a projection lens for magnifying and projecting a display image of the video source on the transmissive screen. A transmissive screen.

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