Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
130 words
A projection television apparatus comprising: three cathode-ray tubes of red, green and blue, respectively which are placed relative to each other to form the letter "T" with their faceplates close to each other and facing each other so that said cathode-ray tubes of red and blue are placed in the same plane and on either side of said cathode-ray tube of green, a mirror block which comprises a red-type dichroic mirror and a blue-type dichroic mirror reflecting exclusively red light and blue light, respectively and intersecting to form the letter "X", and which is placed in the parallelepipedal space formed by said faceplates, and a lens which is placed on the optical axis of said cathode-ray tube of green, characterized in that said mirror block is movable to effect focussing.
Claim 2
Dependent Claim
130 words
A projection television apparatus comprising: three cathode-ray tubes of red, green and blue, respectively which are placed relative to each other to form the letter "T" with their faceplates close to each other and facing each other so that said cathode-ray tubes of red and blue are placed in the same plane and on either side of said cathode-ray tube of green, a mirror block which comprises a red-type dichroic mirror and a blue-type dichroic mirror reflecting exclusively red light and blue light, respectively and intersecting to form the letter "X", and which is placed in the parallelepipedal space formed by said faceplates, and a lens which is placed on the optical axis of said cathode-ray tube of green, characterized in that said mirror block is movable to effect focussing.
Claim 3
Dependent Claim
35 words
A projection television apparatus as claimed in claim 1, wherein said mirror block can move parallel without changing any angle between a normal of said dichroic mirrors and an optical axis of said cathode-ray tubes.
Claim 4
Dependent Claim
96 words
A projection television apparatus as claimed in claim 2, wherein a base section (24) is placed at the bottom of said parallelepipedal space between the faceplates, a centre section (25) is placed on said base section, an upper section (26) is placed on said centre section, and said mirror block (13) is fixed on said upper section, said base section and said centre section having a co-operating protuberance (29) and groove (33) on their touching surfaces, and said centre section and said upper section having a co-operating protuberance (30) and groove (34) on their touching surfaces.
Claim 5
Dependent Claim
61 words
A projection television apparatus as claimed in claim 3, wherein said centre section (25) can slide over said base section (24) in a direction parallel to the plane of one of said dichroic mirrors (18,19), and said upper section (26) can slide over said centre section (25) in a direction parallel to the plane of the other of said dichroic mirrors.
Claim 6
Dependent Claim
48 words
5 0 A projection television apparatus as claimed in claim 4, wherein said centre section (25) consists of two strips (35,36) which are fixed to each other to form the letter "X", and said base section (24) and upper section (26) have grooves (50,42) for receiving said strips.