Split unit

Patent metadata

Field	Value
Publication number	US-9323062-B2
Application number	US-201414571750-A
Country	US
Kind code	B2
Filing date	Dec 16, 2014
Priority date	Jun 18, 2012
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

A split unit capable of providing a stereoscopic image having less laterality is provided. The split unit includes: a beam splitter which transmits first imaging light as a part of light incident on an incident surface of the beam splitter, and reflects second imaging light as another part of the light incident on the incident surface; and a reflecting member which reflects the second imaging light reflected by the beam splitter. At least one of a reflectance of the reflecting member and a beam splitting characteristic of the beam splitter is set based on the following formulae:

T=d /(1+ d )

R =1− T
where T (0≦T≦1) is a transmittance of the beam splitter, R (0≦R≦1) is a reflectance of the beam splitter, and d (0≦d≦1) is a reflectance of the reflecting member.

First claim

What is claimed is:

1. A split unit comprising:
a beam splitter which transmits first imaging light as a part of light incident on an incident surface of the beam splitter, and reflects second imaging light as another part of the light incident on the incident surface; and
a reflecting member which reflects the second imaging light reflected by the beam splitter, wherein
at least one of a reflectance of the reflecting member and a beam splitting characteristic of the beam splitter is set based on the following formulae:
T=d /(1+ d )
R= 1− T

where
T (0≦T≦1) is a transmittance of the beam splitter,
R (0≦R≦1) is a reflectance of the beam splitter, and
d (0≦d≦1) is a reflectance of the reflecting member.

2. The split unit according to claim 1 , wherein
a beam splitting ratio of the beam splitter is set such that when light having a predetermined design center wavelength is incident on the beam splitter, the amount of the second imaging light reflected by the reflecting member and the amount of the first imaging light transmitted through the prism are substantially equal to each other, and when light having a wavelength in a visible region other than the design center wavelength is incident on the beam splitter, the beam splitting ratio is within a predetermined allowable range.

3. The split unit according to claim 1 , wherein
at least one of the reflectance of the reflecting member and the beam splitting characteristic of the beam splitter is set such that a difference between brightness of an image formed by the second imaging light reflected by the reflecting member and brightness of an image formed by the first imaging light transmitted through the prism is not smaller than 0% but not larger than 35%.

4. The split unit according to claim 1 , wherein
the beam splitting ratio of the beam splitter is set based on the average of transmittances of P-polarized light and S-polarized light.

5. The split unit according to claim 4 , wherein
the beam splitting ratio of the beam splitter is set based on the average of transmittances of P-polarized light beams having a plurality of incident angles and S-polarized light beams having a plurality of incident angles.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Nagaishi Yuji
• Shimazaki Hiroaki
• Tsuda Kenjiro
• Masuno Takashi
• Kajino Osamu

Classifications

• G03B35/08

  by simultaneous recording · CPC title

• H04N13/214

  using spectral multiplexing · CPC title

• G02B27/14

  operating by reflection only · CPC title

• G02B5/04

  Prisms · CPC title

• G03B35/10

  having single camera with stereoscopic-base-defining system · CPC title