Development of Ultimate Transmitting Dispersive Grating (Grism)

终极透射色散光栅（Grism）的开发

基本信息

批准号：
09559018
负责人：
SASAKI Toshiyuki
金额：
$ 8.64万
依托单位：
National Astronomical Observatory
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

Research and development of high efficiency prisms (transmitting gratings ruled on prisms) were carried out for implementation at Faint Object Camera And Spectrograph FOCAS and for Coronagraphic Imager with Adaptive Optics CIAO both to be mounted on the 8.2m Subaru telescope.First of all, a measuring system was set up to evaluate the ruling shape of grisms through the FFT of the intensity distribution of diffracted light. This system was then expanded to enable absolute measurement of efficiency in diffracted beams. Fabrication of grisms for CIAO, to be used in the near infrared wavelength, was tested by ruling grooves directly on infrared transmitting material made of fluorine resine using a hyper fine 3D machining system. The grism actually fabricated in this way has shown to give 65-70% diffraction efficiency in the near infrared. Low dispersion and medium dispersion grisms for FOCAS and for Trispec were made by using the standard replicating method on resin material deposited on glass base plates and was shown to give 80% diffraction efficiency.Grisms made of high refractive index material are required for high dispersion grisms of FOCAS and for CIAO spectroscopic modes. Various methods were tested to produce deep grooves on optical material with refractive index larger than 1.9, but no promising method has yet been identified.Germanium grisms are useful in making the size of the high dispersion spectrograph for infrared small enough to save the cost and to enhance the stability of such an instrument. It was shown in this study that such a grism actually manufactured shows acceptable performance in 10 micron wavelength application but the surface roughness is of concern for use at 2 micron wavelength.

Research and development of high efficiency prisms (transmitting gratings ruled on prisms) were carried out for implementation at Faint Object Camera And Spectrograph FOCAS and for Coronagraphic Imager with Adaptive Optics CIAO both to be mounted on the 8.2m Subaru telescope.First of all, a measuring system was set up to evaluate the ruling shape of grisms through the FFT of the intensity distribution of diffracted light.然后扩展该系统，以实现衍射光束中效率的绝对测量。通过直接使用超细3D加工系统对红外发射材料进行裁定，对CIAO的Gristation用于CIAO的Grastation用于近红外波长中。实际以这种方式捏造的gr狂已显示出在近红外的65-70％衍射效率。通过对沉积在玻璃底板上的树脂材料上使用标准复制方法，制造了焦点和TRISPEC的低分散和中等分散剂，并被证明具有80％的衍射效率。高屈光度指标材料需要高折射率材料制成的高分子分散剂，用于焦点和ciao光谱模态。测试了各种方法，以对具有大于1.9的折射率的光学材料产生深层凹槽，但尚未鉴定出有希望的方法。GrismaniumGrisms有助于使高分散光谱仪的大小适用于高度的高度小型，以节省足够的成本，以节省其成本并增强这种仪器的稳定性。这项研究表明，这种grism实际上在10微米波长应用中表现出可接受的性能，但表面粗糙度值得在2微米波长下使用。