Exposure controlling means for a variable focus type camera

Claim 2

An exposure controlling means for a camera with a variable focal length lens of which the open aperture value changes as the focal length changes, characterised by means for controlling the exposure, depending upon the prescribed film speed and the photometered value, with reference to one source of data, corrected or not according to the focal length instantaneously employed.

Claim 3

An exposure controlling means according to claim 1, characterised in that the source of data prescribes the relations between shutter speeds and photometered values and film speeds, for one focal length.

Claim 4

The exposure controlling means according to claim 1 or 2 characterised by a memory means (5,75) for memorising said table storing thereon the relations between photometered values and shutter speeds, a focal length information detecting means (S(W)(S(T)) for giving a focal length information of a taking lens, a photometering means (2,73) for detecting a subject brightness, and a controlling means (1,74) for controlling a shutter (14) in the manner that a photometered value on the table contained in said memory means (5,75) is shifted by a difference of the open aperture values between one prescribed focal length and the other prescribed focal length, in accordance with the information given from said focal length information detecting means (S(W)S(T)) and said photometering means (2,73), so as to read the most suitable shutter speed.

Claim 5

The exposure controlling means as claimed in any of claims 1, 2 or 3 characterised in that the focal length of said variable focal length lens is changed by reciprocating the lens in the direction of the optical path thereof and in that said focal length information detecting means (S(W)S(T)) comprises a switching means (S(W)S(T)) for detecting the position of said lens.

Claim 6

An exposure controlling means for use with a variable focus type camera characterised by photometering means (2,73) for detecting a subject brightness, film speed information means (3,70) for giving a signal corresponding to a film speed, focal length information detecting means (S(T), S(W)), for giving a focal length information of the variable focal lens, memorising means (5,75) for memorising a table storing thereon shutter speeds corresponding to film speeds and photometered values with respect to the prescribed focal lengths, and controlling means (1,74) for controlling a means for operating aperture blades and a shutter in combination in the manner that the most suitable shutter speed is read from the table in said memorising means (5,75) in accordance with subject brightness information from said photometering means (2,73), focal length information, corresponding to the focal length used from said focal length information detecting means (S(W), S(T)) and film speed information from said film speed information means (3,70).

Claim 7

An exposure controlling means for use with a variable focus type camera characterised by photometering means (2,73) for detecting a subject brightness, film speed information means (3,70) for giving a signal corresponding to a film speed, focal length information detecting means (S(T), S(W)), for giving a focal length information of the variable focal lens, memorising means (5,75) for memorising a table storing thereon shutter speeds corresponding to film speeds and photometered values with respect to the prescribed focal lengths, and controlling means (1,74) for controlling a means for operating aperture blades and a shutter in combination in the manner that the most suitable shutter speed is read from the table in said memorising means (5,75) in accordance with subject brightness information from said photometering means (2,73), focal length information, corresponding to the focal length used from said focal length information detecting means (S(W), S(T)) and film speed information from said film speed information means (3,70).

Claim 8

The exposure controlling means as claimed in claim 5, characterised in that said controlling means (1,74) controls said means for operating aperture blades and a shutter in combination (14) in the manner that a film speed on the table stored in said memorizing means (5,75) is shifted by a prescribed value corresponding to a film speed value derived from said film speed information means (3,70) in accordance with the changes of the open aperture value corresponding to a prescribed focal length in keeping with the changes of the focal lengths of said variable focus lens, and then a shutter speed determined by the shifted film speed is read.

Claim 9

The exposure controlling means as claimed in claim 5, characterised in that said controlling means (1,74) controls said means for operating aperture blades and a shutter in combination (14) in the manner that a photometered value on the table stored in said memorising means (5,75) is shifted by a prescribed value corresponding to a photometered value derived from said photometering means (2,73) in accordance with the changes of the open aperture value corresponding to the focal length of the lens being used in keeping with the changes of the focal lengths of said variable focus lens, and then a shutter speed determined by a film speed information given from said film speed information means (3,70) and the shifted photometered value is read.

Claim 10

The exposure controlling means according to any of claims 5 to 7 characterised in that the table stored in said memorising means (5,75) is arranged in a matrix system in accordance with APEX indices, and the photometered values are arbitrarily segmented thereon in accordances with the APEX indices corresponding to the respective film speeds.

Claim 11

An exposure controlling means for use with a camera equipped with a variable focal point lens of which the open aperture value is changed by changing the focal length of the lens characterised by a flash means (7,76), a photometering means (2,73) for detecting a subject brightness, a distance measuring means (6,71) for detecting a camera-to-subject distance, a film speed information means (3,70) for sending a signal corresponding to a film speed, a focal length information detecting means (s(T), s(W)), for a variable focal point lens, a memorising means (5,75) for memorising a table storing both of a shutter speed corresponding to a film speed and a photometered value each at a prescribed focal length and a shutter speed corresponding to a film speed and a camera-to-subject distance zone each, and a controlling means (1,74) for controlling both of said means for operating shutter blades and a shutter in combination (14) and a flash timing of said flash means (7,76) in a flash photography in the manner that the most suitable shutter speed is read from the table in said memorising means (5,75) in accordance with a camera-to-subject distance information given from said distance measuring means, a changed value corresponding to a prescribed focal length in a focal length information given from said focal length information detecting means (s(W), s(T)) and a film speed information given from said film speed information means (3,70).

Claim 12

An exposure controlling means for use with a camera equipped with a variable focal point lens of which the open aperture value is changed by changing the focal length of the lens characterised by a flash means (7,76), a photometering means (2,73) for detecting a subject brightness, a distance measuring means (6,71) for detecting a camera-to-subject distance, a film speed information means (3,70) for sending a signal corresponding to a film speed, a focal length information detecting means (s(T), s(W)), for a variable focal point lens, a memorising means (5,75) for memorising a table storing both of a shutter speed corresponding to a film speed and a photometered value each at a prescribed focal length and a shutter speed corresponding to a film speed and a camera-to-subject distance zone each, and a controlling means (1,74) for controlling both of said means for operating shutter blades and a shutter in combination (14) and a flash timing of said flash means (7,76) in a flash photography in the manner that the most suitable shutter speed is read from the table in said memorising means (5,75) in accordance with a camera-to-subject distance information given from said distance measuring means, a changed value corresponding to a prescribed focal length in a focal length information given from said focal length information detecting means (s(W), s(T)) and a film speed information given from said film speed information means (3,70).

Claim 13

Exposure controlling means as claimed in claim 9, characterised in that said controlling means (1;74) controls both of said means for operating aperture blades and a shutter in combination (14) and an electronic flash (7,76) operation in the manner that a film speed on the table stored in said memorising means (5,75) is shifted by a prescribed value corresponding to a film speed value inputted from said film speed information means in accordance with the changes of the open aperture value corresponding to a prescribed focal length involved in keeping with the changes of the focal lengths of said variable focus lens, and then a shutter speed is read as is determined by both of a camera-to-subject distance selected in accordance with a camera-to-subject distance information given from said distance measuring means (6,71) and the shifted film speed.

Claim 14

Exposure controlling means according to claim 9 or 10, characterised in that the table stored in said memorising means (5,75) is arranged in a matrix system in accordance with APEX indices, and the camera-to-subject distance zones are arbitrarily segmented in accordance with APEX indices corresponding to film speeds.