公开(公告)号：DE3125205A1

公开(公告)日：1982-03-11

申请号：DE3125205

申请日：1981-06-26

Applicant: CANON KK

Inventor： SUZUKI TAKASHI ,  IIZUKA KIYOSHI ,  OHTAKA KEIJI ,  MIZUTANI HIDEMASA

IPC: G02B5/02 ,  G03B13/24

Abstract: This application relates to a diffusion plate having microlens-like curved surfaces of a size of 10 to several tens of mu m arranged periodically in two dimensions on the surface of the substrate thereof. Curved surfaces are formed between the microlens-like curved surfaces. Further, irregularly arranged minute concave and/or convex surfaces are formed on the microlens-like curved surfaces.

公开(公告)号：DE3125317A1

公开(公告)日：1982-04-01

申请号：DE3125317

申请日：1981-06-27

Applicant: CANON KK

Inventor： SUZUKI TAKASHI ,  IIZUKA KIYOSHI ,  OHTAKA KEIJI ,  MIZUTANI HIDEMASA

IPC: G02B5/02 ,  G03B13/24

Abstract: A focussing plate for photographic cameras, etc. which is constructed with a multitude of micro-lens shaped curved surfaces arranged on a substrate surface at a space interval among them of from 5 to 30 mu m, and other curved surfaces arranged in the boundary spaces among these micro-lens shaped curved surfaces having a curvature just opposite to that of the micro-lens shaped curved surfaces.

公开(公告)号：JPH0342621A

公开(公告)日：1991-02-22

申请号：JP17739089

申请日：1989-07-10

Applicant: CANON KK

Inventor： FUSHIMI MASAHIRO ,  IIZUKA KIYOSHI

IPC: G03B13/24 ,  G02F1/13 ,  G02F1/1333

Abstract: PURPOSE:To form a high-grade focus by using a liquid crystal element disposed with gap spacers on the outside of the region of a finder visual field as the focal plate. CONSTITUTION:This focal plate has a layer 23 formed by dispersing and incorporating a nematic liquid crystal having a positive dielectric anisotropy into a transparent high-polymer material having no dielectric anisotropy and a pair of transparent substrates 29, 30 which have the transparent electrodes at least in a part thereof and crimp the layer 23. The focal plate for cameras consists of the liquid crystal element which consists of the structure to set the spacing between the transparent substrates 29 and 30 by interposing the gap spacers 26 between a pair of the transparent substrates and can control the diffusivity of the quantity of the transmitted light by voltage impression to the transparent electrodes 22, 24. The gap spacers 26 are disposed on the outside of the region where the finder visual field of the liquid crystal element is delineated. The formation of the high-grade focus is possible in this way and the similar diffusion characteristics and transmission characteristics to various kinds of polarized light are obtd.

公开(公告)号：JPH02118536A

公开(公告)日：1990-05-02

申请号：JP27088488

申请日：1988-10-28

Applicant: CANON KK

Inventor： FUSHIMI MASAHIRO ,  IIZUKA KIYOSHI

IPC: G03B13/24 ,  G02F1/13

Abstract: PURPOSE:To facilitate control by providing a means for controlling a scattering property by an impressed voltage and controlling the polarizing state of the incident light or exit light of the liquid crystal layer of the focus plate. CONSTITUTION:A light distributing film 14 is provided to a transparent substrate 15 having grid-shaped transparent electrodes 11, 12 to homogeneously orient liquid crystal molecules. This liquid crystal layer 13 is crimped by a pair of the transparent substrates 15 facing each other. The liquid crystal molecules are arranged in the direction of an electric field when a voltage is impressed thereto. A refractive index distribution is formed according to the electric field distribution arising from the periods of the grid-shaped electrodes 11, 12 by the double refractive indices of the liquid crystal molecules and the liquid crystal cell forms the diffused state of light at this time. Further, the grade of the diffused state is enhanced if a rotatable polarizing plate 16 is provided to the liquid crystal focus plate. The control of the incident light or reflected light of the liquid crystal layer 13 by rotation of the polarizing plate 16 can be executed by changing the impressed voltage. The easy control of the focus plate is executed with the simple constitution in this way.

公开(公告)号：JPH0272323A

公开(公告)日：1990-03-12

申请号：JP22249388

申请日：1988-09-07

Applicant: CANON KK

Inventor： FUSHIMI MASAHIRO ,  IIZUKA KIYOSHI

IPC: G03B13/24 ,  G02F1/13

Abstract: PURPOSE:To provide the focal plate which is well visible even in a diffusion state and transmission state, allows easy focusing in the diffusion state and has a high grade by forming the high-polymer film in the peripheral part of the focal plate of a liquid crystal element formed by dispersing a nematic liquid crystal into the high-polymer film to the thickness smaller than the thickness of the central part. CONSTITUTION:The film 13 formed by dispersing the nematic liquid crystal having positive dielectric anisotropy into the high polymer which exhibits the refractive index equal to the refractive index of the liquid crystal to ordinary light and has no dielectric anisotropy is crimped by transparent substrates 15, 16 having a pair of transparent electrodes 11, 12 facing each other. The control of the diffusion state and transmission state is executed by the voltage to be impressed to the conductive films 11, 12. The focal plate having the high grade is obtd. in this way and the decrease of the quantity of the light in the peripheral part by the spread of the diffused light is prevented.

公开(公告)号：JPS6474535A

公开(公告)日：1989-03-20

申请号：JP23090387

申请日：1987-09-17

Applicant: CANON KK

Inventor： FUSHIMI MASAHIRO ,  IIZUKA KIYOSHI

IPC: G03B13/24

Abstract: PURPOSE:To suppress reduction in light quantity in peripheral parts and to form images of uniform brightness on the entire surface of a reticle by forming two or more types of synchronization in terms of a change in refraction factors and making the changing quantity of phase distribution in peripheral areas smaller than that in the central part. CONSTITUTION:The reticle is constituted in that a transparent electrode obtained by patterning a liquid crystal layer, which changes between an array nearly in parallel with the surface of a substrate and an array nearly perpendicular to said surface to correspond with the intensity of an impressed electric field, is sealed between pair glass substrates fully deposited. With said reticle, the pattern of an electrode part 1 comes in two formed periodical areas A and B: the former represents an area of great electrode period and the latter does an area of low electrode period. By adjusting an impressed voltage, a desired phase change is available. The changing quantity of phase in the peripheral areas is made smaller than that in the central part, whereby dispersion in the peripheral part is suppressed and reduction in light quantity in the peripheral part owing to the spreading of diffused light is prevented. Therefore images of uniform brightness can be formed on the entire surface of the reticle.

公开(公告)号：JPS63259512A

公开(公告)日：1988-10-26

申请号：JP9489087

申请日：1987-04-16

Applicant: CANON KK

Inventor： KAWATE SHINICHI ,  IIZUKA KIYOSHI ,  FUJIWARA RYOJI ,  FUSHIMI MASAHIRO

IPC: G02F1/13

Abstract: PURPOSE:To make the inside of a finder bright and easy to visible by extending a power supply period after having opened a power source switch or after having ended a shutter operation, executing an electric conduction of the reverse direction to a material optical element of a variable ND filter, and resetting it to a light transmission state. CONSTITUTION:When a camera is started, first of all, the incident light quantity is measured by a photosensor 20, and it is transferred to an automatic control circuit 12 of a variable ND filter 11. The automatic control circuit 12 calculates a proper value of a shutter speed, a diaphragm value, etc., executes an electric conduction to the variable ND filter 11 so as to correspond to said value, and sets it to a transmittivity attenuating state. That is, first electrochromic layers 3, 3' are colored in black, and after the electric conduction is cut off, the density is maintained by a memory action. After the shutter operation is ended, a current in the direction opposite to the time of coloring is brought to an electric conduction to the variable ND filter 11 from the automatic control circuit 12, and it is reset to a light transmission state. In such a way, it does not occur that the inside of a finder is dark and scarcely seen.

公开(公告)号：JPS63141026A

公开(公告)日：1988-06-13

申请号：JP28684686

申请日：1986-12-03

Applicant: CANON KK

Inventor： IIZUKA KIYOSHI ,  NAGANO AKIHIKO

IPC: G02B27/46 ,  G02F1/133

Abstract: PURPOSE:To always obtain a MODULATION TRANSFER FUNCTION MTF which is invariably stable even when the temperature drops by constituting such a circuit that the value of a driving voltage has a negative coefficient to the temperature. CONSTITUTION:A rectangular wave outputted by an oscillator 15 is made into a constant-voltage rectangular wave by a voltage correcting circuit 16 and outputted. A temperature compensating amplifier 17 outputs a temperature- corrected voltage by a thermistor 19 with a negative resistance temperature coefficient and the voltage is applied to a liquid crystal optical phase filter 4. If the ambient temperature is low and the viscosity of liquid crystal is high at this time, a higher voltage than usual is applied, and as the temperature rises, the applied voltage is made lower. Consequently, the MTF is held invariable constant regardless of variation in the ambient temperature.

公开(公告)号：JPS63132217A

公开(公告)日：1988-06-04

申请号：JP27871686

申请日：1986-11-25

Applicant: CANON KK

Inventor： IIZUKA KIYOSHI ,  NAGANO AKIHIKO

IPC: G02F1/13

Abstract: PURPOSE:To switch a soft and a sharp image without changing filters by sandwiching a liquid crystal layer which changes in orientation by being applied with an electric field between substrates as a liquid crystal optical phase member, providing a rotatable polarizing plate nearby this member, and adjusting the electric field application and the angle of the polarizing plate. CONSTITUTION:The liquid crystal optical phase filter consists of the liquid crystal layer 9 which changes in orientation according to whether or not an electric field is applied, two transparent electrodes 7 and 8 which apply the electric field to this liquid crystal layer, and the polarizing plate 16 which controls luminous flux incident on or projected from the liquid crystal layer. Opening parts 7a which are distributed at random are formed in at least one transparent electrode between those two transparent electrodes 7 and 8 and the polarizing plate 16 is made relatively rotatable to the liquid crystal layer to control the birefringence of the liquid crystal layer and the polarized component ratio of the incident light to or projection light from the liquid crystal layer, thereby varying a modulation Transfer Function MTF value optionally. Consequently, when this filter is mounted in front of a camera lens once, a soft and a sharp image can be switched without detaching the filter.

公开(公告)号：JPS6371803A

公开(公告)日：1988-04-01

申请号：JP15301487

申请日：1987-06-19

Applicant: CANON KK

Inventor： SUZUKI TAKASHI ,  IIZUKA KIYOSHI

IPC: G02B5/02 ,  G03B13/24

Abstract: PURPOSE:To obtain a diffusion board recorded with speckle patterns of a same size by setting the diameter of a circle inscribing the zonal opening of a light shielding plate and a center distance between inscribed circles which are separated most among the inscribed circles to a value within a prescribed range. CONSTITUTION:A light beam from a light source 12 such as an He-Ne laser illuminates the diffusion board 14 through an illumination lens 13 and converges the light flux in the center of an image-forming lens 15. The light shielding plate 16 has the zonal opening, which sets the diameters (d) of the small circles 25 and 26 touching the verge of the zonal opening 24, and the center distance D of the small circles 25 and 26 to the relation of 1