US 7,248,234 B2 · Image display apparatus having delta arrangement type screen and image conversion method for display

Abstract

In order to reduce aliasing as much as possible in a display apparatus that has a delta arrangement type screen, an image filter for performing a neighborhood operation is incorporated as a previous stage of a screen driving circuit. The image filter realizes low pass filtering including space frequency limitation in the diagonal direction that is suitable for a display on the delta arrangement type screen. Coefficients that constitute the filter matrix are optimized so that frequency components that exceed a Nyquist limit in the delta arrangement are suppressed. Coefficients that give optimal filter characteristics for any scale of filter matrix are defined by an expression.

Claims20

Dependent claims

An image display apparatus for displaying an input image whose pixel arrangement is an orthogonal arrangement by converting the image into an image in a non-orthogonal arrangement, the apparatus comprising:

a display device having a non-orthogonal arrangement type screen on which an electrode matrix for controlling a display is arranged;
a band limitation filter for performing an operation for narrowing a space frequency range of image data that represent the input image;
an arrangement conversion circuit for performing an operation for converting a pixel arrangement of an output of the band limitation filter from the orthogonal arrangement into a cell arrangement of the screen;
and
a driving circuit for applying a drive voltage to the electrode matrix in accordance with an output of the arrangement conversion circuit.

2 more elements

a display device having a non-orthogonal arrangement type screen on which an electrode matrix for controlling a display is arranged;
an image conversion circuit for performing an add operation with weighting that is for narrowing a space frequency range of image data that represent the input image and is for converting the pixel arrangement from the orthogonal arrangement into a cell arrangement of the screen;
and
a driving circuit for applying a drive voltage to the electrode matrix in accordance with an output of the image conversion circuit.

1 more element

An image conversion method that is used for a display by a delta arrangement type screen including a plurality of pixels, the method comprising:

performing a neighborhood operation for calculating display luminance values of the pixels on the screen from luminance values at N data points in the input image as an operation for converting an input image into an image whose space frequency is limited;
making a data point pitch in the vertical direction of the input image be a half of a pixel pitch y0 in the vertical direction of the screen and a data point pitch in the horizontal direction of the input image be a half of a pixel pitch x0 in the horizontal direction of the screen;
and
multiplying a luminance value at the data point of the input image by a coefficient ρj in the neighborhood operation, the coefficient ρj being defined by the following expression
ρ
j
=
1
N
⁢
{
1
2
⁢
∑
j
⁢
ω
j
+
1
}
-
1
2
⁢
ω
j
where ωj is an integral value within an area σ of a preset Nyquist limit, which is defined by the following expression
ω
j
=
-
x
0
⁢
y
0
2
⁢
∫
σ
⁢
exp
⁡
(
-
2
⁢
⁢
π
⁢
⁢
ⅈ
⁢
⁢
μ
⁢
⁢
ξ
j
)
⁢
⁢
exp
⁡
(
-
2
⁢
⁢
π
⁢
⁢
ⅈ
⁢
⁢
v
⁢
⁢
ψ
j
)
⁢
ⅆ
μ
⁢
ⅆ
v
where ξj and ψj are components of coordinates (ξj,ψj) of a position of the coefficient ρj with respect to a pixel whose intensity is to be calculated, while μ and ν are components of coordinates (μ,ν) in a frequency space.

87 more elements

An image conversion method that is used for a display by a delta arrangement type screen including a plurality of pixels, the method comprising:

performing a neighborhood operation for calculating display luminance values of the pixels on the screen from luminance values at N data points in the input image as an operation for converting an input image into an image whose space frequency is limited;
making a data point pitch in the vertical direction of the input image be not a half of a pixel pitch y0 in the vertical direction of the screen or a data point pitch in the horizontal direction of the input image be not a half of a pixel pitch x0 in the horizontal direction of the screen;
and
multiplying a luminance value at the data point of the input image by a coefficient ρj in the neighborhood operation, the coefficient ρj being defined by the following expression
p
l
=
∑
j
⁢
χ
l
⁢
⁢
j
-
1
∑
j
,
k
⁢
χ
j
⁢
⁢
k
-
1
⁢
{
1
2
⁢
∑
j
,
k
⁢
χ
j
⁢
⁢
k
-
1
⁢
ω
k
+
1
}
-
1
2
⁢
∑
j
⁢
χ
l
⁢
⁢
j
-
1
⁢
ω
j
where ωj is an integral value within an area σ of a preset Nyquist limit, which is defined by the following expression
ω
j
=
-
x
0
⁢
y
0
2
⁢
∫
σ
⁢
exp
⁡
(
-
2
⁢
⁢
π
⁢
⁢
ⅈ
⁢
⁢
μ
⁢
⁢
ξ
j
)
⁢
⁢
exp
⁡
(
-
2
⁢
⁢
π
⁢
⁢
ⅈ
⁢
⁢
v
⁢
⁢
ψ
j
)
⁢
ⅆ
μ
⁢
ⅆ
v
where ξj and ψj are components of coordinates (ξj,ψj) of a position of the coefficient ρj with respect to a pixel whose intensity is to be calculated, while μ and ν are components of coordinates (μ,ν) in a frequency space, while χ−1jk is an inverse matrix of a matrix χjk that is defined by an integral value within an integral area determined by ωj and a pixel pitch and
χ
j
⁢
⁢
k
=
x
0
⁢
y
0
4
⁢
∫
-
1
/
y
0
1
/
y
0
⁢
∫
-
1
/
x
0
1
/
x
0
⁢
exp
⁡
(
2
⁢
⁢
π
⁢
⁢
ⅈ
⁢
⁢
μ
⁡
(
ξ
j
-
ξ
k
)
)
⁢
exp
⁡
(
2
⁢
⁢
π
⁢
⁢
ⅈ
⁢
⁢
v
⁡
(
ψ
j
-
ψ
k
)
)
⁢
⁢
ⅆ
μ
⁢
ⅆ
v

215 more elements

Dependencies are inferred from the claim text.

Image display apparatus having delta arrangement type screen and image conversion method for display

Life of this patent

Image display apparatus having delta arrangement type screen and image conversion method for display

Life of this patent

Abstract

Claims20