US 7,252,392 B2Granted

Illumination apparatus and image projection apparatus using the illumination apparatus

AssigneeOlympus Corporation

InventorShinzo Matsui

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Abstract

An illumination apparatus which applies light from light emitting members to a region to be illuminated. The apparatus includes an emitted light quantity control unit which controls emitted light quantities of the members, and a light transmissibility changing unit which controls transmissibility of each light path which transmits output light of the light emitting member to the region. The controls of the emitted light quantity control unit and the light transmissibility changing unit are performed in such a manner that an illuminative light quantity in the region during intermittent lighting of a predetermined number of light emitting members which are some of the light emitting members at a driving current value larger than a rated current in a predetermined period is larger than an illuminative light quantity in the region during constant lighting of the predetermined number of light emitting members at a rated driving current in the predetermined period.

Claims16

Dependent claims

An illumination apparatus which applies light from light sources to a region to be illuminated, comprising:

a plurality of light emitting members which are the light sources;
an emitted light quantity control unit configured to control emitted light quantities of the plurality of light emitting members;
and
a light transmissibility changing unit configured to be capable of controlling transmissibility of each light path which transmits output light of the light emitting member to the region to be illuminated;
wherein:
the emitted light quantity control unit controls the emitted light quantity and the light transmissibility changing unit controls the transmissibility in such a manner that an illuminative light quantity P in the region to be illuminated during intermittent lighting of a predetermined number n of light emitting members which are some of the plurality of light emitting members at a driving current value larger than a rated current in a predetermined period T is larger than an illuminative light quantity P-typ in the region to be illuminated during constant lighting of the predetermined number n of light emitting members at a rated driving current I-typ in the predetermined period T;
the emitted light quantity control unit is configured to control a light emission timing, a light emission time, and a driving current value in such a manner that three factors are correlated with one another in a case where the light emitting members are allowed to intermittently emit the light in accordance with the transmissibility obtained by periodically controlling the transmissibility of each light path by the light transmissibility changing unit;
and
assuming that the number of the light emitting members simultaneously emitting the light is n, the number of each of the n light emitting members simultaneously emitting the light is j, brightness of the n light emitting members at a pulse time supply current Ij-pulse is Lj (t), a ratio of the light quantity of the light of the n light emitting members guided to the region to be illuminated via the light transmissibility changing unit is Kj (t), brightness at a rated current Ij-typ in constant lighting of the n light emitting members is Lj-typ, a ratio of an optimum light quantity, at which the light transmissibility changing unit does not change with time to maximize the illuminative light quantity P-typ is Kj-stop, and a predetermined period is T, the emitted light quantity control unit is configured to control the light emission timing, the light emission time, and the driving current value in the plurality of light emitting members in such a manner as to satisfy the following condition equation:
P
=
∫
0
T
⁢
∑
j
=
1
n
⁢
{
L
j
⁡
(
t
)
×
K
j
⁡
(
t
)
}
⁢
ⅆ
t
>
P
⁢
-
⁢
typ
=
∑
j
=
1
n
⁢
{
L
j
⁢
-
⁢
typ
×
K
j
⁢
-
⁢
stop
}
×
T
⁢
.

68 more elements

An image projection apparatus comprising:

an illumination apparatus which applies light from light sources to a region to be illuminated, including:
a plurality of light emitting members which are the light sources;
an emitted light quantity control unit configured to control emitted light quantities of the plurality of light emitting members;
and
a light transmissibility changing unit configured to be capable of controlling transmissibility of each light path which transmits output light of the light emitting member to the region to be illuminated, the emitted light quantity control unit controlling the emitted light quantity and the light transmissibility changing unit controlling the transmissibility in such a manner that an illuminative light quantity P in the region to be illuminated during intermittent lighting of a predetermined number n of light emitting members which are some of the plurality of light emitting members at a driving current value larger than a rated current in a predetermined period T is larger than an illuminative light quantity P-typ in the region to be illuminated during constant lighting of the predetermined number n of light emitting members at a rated driving current I-typ in the predetermined period T;
an image display element disposed in the region to be illuminated;
and
an optical projection system configured to enlarge and project an image on the image display element:
wherein:
the emitted light quantity control unit is configured to control a light emission timing, a light emission time, and a driving current value in such a manner that three factors are correlated with one another in a case where the light emitting members are allowed to intermittently emit the light in accordance with the transmissibility obtained by periodically controlling the transmissibility of each light path by the light transmissibility changing unit;
and
assuming that the number of the light emitting members simultaneously emitting the light is n, the number of each of the n light emitting members simultaneously emitting the light is j, brightness of the n light emitting members at a pulse time supply current Ij-pulse is Lj (t), a ratio of the light quantity of the light of the n light emitting members guided to the region to be illuminated via the light transmissibility changing unit is Kj (t), brightness at a rated current Ij-typ in constant lighting of the n light emitting members is Lj-typ, a ratio of an optimum light quantity, at which the light transmissibility changing unit does not change with time to maximize the illuminative light quantity P-typ is Kj-stop, and a predetermined period is T, the emitted light quantity control unit is configured to control the light emission timing, the light emission time, and the driving current value in the plurality of light emitting members in such a manner as to satisfy the condition equation:
P
=
∫
0
T
⁢
∑
j
=
1
n
⁢
{
L
j
⁡
(
t
)
×
K
j
⁡
(
t
)
}
⁢
ⅆ
t
>
P
⁢
-
⁢
typ
=
∑
j
=
1
n
⁢
{
L
j
⁢
-
⁢
typ
×
K
j
⁢
-
⁢
stop
}
×
T
⁢
.

71 more elements

An illumination apparatus which applies light from light sources to a region to be illuminated, comprising:

a plurality of light emitting members which are the light sources;
emitted light quantity control means for controlling emitted light quantities of the plurality of light emitting members;
and
light transmissibility changing means for being capable of controlling transmissibility of each light path which transmits output light of the light emitting member to the region to be illuminated,
wherein:
the emitted light quantity control means controls the emitted light quantity and the light transmissibility changing means controls the transmissibility in such a manner that an illuminative light quantity P in the region to be illuminated during intermittent lighting of a predetermined number n of light emitting members which are some of the plurality of light emitting members at a driving current value larger than a rated current in a predetermined period T is larger than an illuminative light quantity P-typ in the region to be illuminated during constant lighting of the predetermined number n of light emitting members at a rated driving current I-typ in the predetermined period T;
the emitted light quantity control means is configured to control a light emission timing, a light emission time, and a driving current value in such a manner that three factors are correlated with one another in a case where the light emitting members are allowed to intermittently emit the light in accordance with the transmissibility obtained by periodically controlling the transmissibility of each light path by the light transmissibility changing means;
assuming that the number of the light emitting members simultaneously emitting the light is n, the number of each of the n light emitting members simultaneously emitting the light is j, brightness of the n light emitting members at a pulse time supply current Ij-pulse is Lj (t), a ratio of the light quantity of the light of the n light emitting members guided to the region to be illuminated via the light transmissibility changing means is Kj (t), brightness at a rated current Ij-typ in constant lighting of the n light emitting members is Lj-typ, a ratio of an optimum light quantity, at which the light transmissibility changing means does not change with time to maximize the illuminative light quantity P-typ is Kj-stop, and a predetermined period is T, the emitted light quantity control means is configured to control the light emission timing, the light emission time, and the driving current value in the plurality of light emitting members in such a manner as to satisfy the following condition equation:
P
=
∫
0
T
⁢
∑
j
=
1
n
⁢
{
L
j
⁡
(
t
)
×
K
j
⁡
(
t
)
}
⁢
ⅆ
t
>
P
⁢
-
⁢
typ
=
∑
j
=
1
n
⁢
{
L
j
⁢
-
⁢
typ
×
K
j
⁢
-
⁢
stop
}
×
T
⁢
;
and
the emitted light quantity control means is configured to control the light emission timing, the light emission time, and the driving current value in such a manner that these three factors are correlated with one another in such a manner as to satisfy the condition equation, when the illuminative light quantity increasing in accordance with the light emission amplification during the light emission of the light emitting member at a driving current larger than the rated current I-typ is set to be lager than the illuminative light quantity decreasing by a drop of the transmissibility accompanying the light transmissibility changing means.

69 more elements

An image projection apparatus comprising:

an illumination apparatus which applies light from light sources to a region to be illuminated, including:
a plurality of light emitting members which are the light sources;
emitted light quantity control means for controlling emitted light quantities of the plurality of light emitting members;
and
light transmissibility changing means for being capable of controlling transmissibility of each light path which transmits output light of the light emitting member to the region to be illuminated, the emitted light quantity control means controlling the emitted light quantity and the light transmissibility changing means controlling the transmissibility in such a manner that an illuminative light quantity P in the region to be illuminated during intermittent lighting of a predetermined number n of light emitting members which are some of the plurality of light emitting members at a driving current value larger than a rated current in a predetermined period T is larger than an illuminative light quantity P-typ in the region to be illuminated during constant lighting of the predetermined number n of light emitting members at a rated driving current I-typ in the predetermined period T;
an image display element disposed in the region to be illuminated;
and
an optical projection system configured to enlarge and project an image on the image display element;
wherein:
the emitted light Quantity control means is configured to control a light emission timing, a light emission time, and a driving current value in such a manner that three factors are correlated with one another in a case where the light emitting members are allowed to intermittently emit the light in accordance with the transmissibility obtained by periodically controlling the transmissibility of each light path by the light transmissibility changing means;
assuming that the number of the light emitting members simultaneously emitting the light is n, the number of each of the n light emitting members simultaneously emitting the light is j, brightness of the n light emitting members at a pulse time supply current Ij-pulse is Lj (t), a ratio of the light quantity of the light of the n light emitting members guided to the region to be illuminated via the light transmissibility changing means is Kj (t), brightness at a rated current Ij-typ in constant lighting of the n light emitting members is Lj-typ, a ratio of an optimum light quantity, at which the light transmissibility changing means does not change with time to maximize the illuminative light quantity P-typ is Kj-stop, and a predetermined period is T, the emitted light quantity control means is configured to control the light emission timing, the light emission time, and the driving current value in the plurality of light emitting members in such a manner as to satisfy the condition equation:
P
=
∫
0
T
⁢
∑
j
=
1
n
⁢
{
L
j
⁡
(
t
)
×
K
j
⁡
(
t
)
}
⁢
ⅆ
t
>
P
⁢
-
⁢
typ
=
∑
j
=
1
n
⁢
{
L
j
⁢
-
⁢
typ
×
K
j
⁢
-
⁢
stop
}
×
T
⁢
;
and
the emitted light quantity control means is configured to control the light emission timing, the light emission time, and the driving current value in such a manner that these three factors are correlated with one another in such a manner as to satisfy the condition equation, when the illuminative light quantity increasing in accordance with the light emission amplification during the light emission of the light emitting member at a driving current larger than the rated current I-typ is set to be lager than the illuminative light quantity decreasing by a drop of the transmissibility accompanying the light transmissibility changing means.

72 more elements

Dependencies are inferred from the claim text.