Theoretic analysis show that the changes of groove density, line-profile and grating substrate(blank) shapes endow gratings the ability of focusing and reducing aberration, so the amount of reflective mirrors are decreased, the efficiency and resolving power of instruments are improved.

As a result of shape change and groove density variation,it not only improves the focusing condition,but also affectes higher order aberrations such as coma aberration of the imaging system.

The geometry theory of holographic variable line space(VLS) gratings was briefly described. The essential condition which the groove density distribution equation obtained by holographic recording must be in agreement with the expected equation after analysis of the varying coefficient of line space and the limitations of the holographic recording parameters on the groove density distribution equation.

Consequently,the long trace profiler was used to test the curved substrates precisely and the groove density of the gratings were measured by diffractive method.

Various methods for the recording of blazed holographic diffraction gratings are presented and the regions in the wavelength-groove density plane for which they can be used are shown.

The investigated variables are: pulse energy, delay time, integration time, grating groove density, object lens distance deviation and crater depth.

In high-resolution spectra of fast ion beams, employing a grating of high groove density in a 2m grazing-incidence monochromator, asymmetric line broadening has been observed.

The MLD grating based Petawatt compressor necessitates a new pulse stretcher using the same groove density as the compressor gratings.

The use of low-groove density gratings makes it more practical to obtain a large spectral bandpass.

The groove density parameters are important to VLS plane gratings monochromator. It is necesary to make sure that the parameters were specified and their errors were acceptable. A diffraction method was used to measure the groove density of VLS grating for system. It included a light source (He - Ne laser), a collimator, a goniometer with angle encoder, a autocollimator, a linear stages, a detector(CCD) and the guting to be tested. The main error sources in the measuring system were analyzed in...

The groove density parameters are important to VLS plane gratings monochromator. It is necesary to make sure that the parameters were specified and their errors were acceptable. A diffraction method was used to measure the groove density of VLS grating for system. It included a light source (He - Ne laser), a collimator, a goniometer with angle encoder, a autocollimator, a linear stages, a detector(CCD) and the guting to be tested. The main error sources in the measuring system were analyzed in details. It turned out that the measuring system proposed was adequated for our purpose. A compensation method was analyzed for the monochromator if the groove density parameters were deviated from the design value.

Varied-line-space grating is very useful in synchrotron radiation devices and laser fusion devices, but there are no good ways to measure them. The line density of varied-line-space gratings have been measured by using interferometry. The principle and geometry are introduced, the methods of data processing and the results are given. On the surface of grating to be tested, quantity and density of diffracted light interferometric fringes are difference of interferometric fringes of incident light and grating...

Varied-line-space grating is very useful in synchrotron radiation devices and laser fusion devices, but there are no good ways to measure them. The line density of varied-line-space gratings have been measured by using interferometry. The principle and geometry are introduced, the methods of data processing and the results are given. On the surface of grating to be tested, quantity and density of diffracted light interferometric fringes are difference of interferometric fringes of incident light and grating groove quantity multiplied. Two sets of waves are in the common path, it is easier to make adjustment and measurement. Interference in interferometric image is removed by mid-value filtering method. Two projects are put forward for different interference fringes. The invariance of relative density is brought forward. The grating diffracts two coherent incident waves, the fringes appear, the density relates to groove density, if the incidence angles and the diffraction orders and the position of fringes are known, the groove density can be calculated. The method can satisfy the requirements of varied-line-space gratings, and it is suitable in the measurement of varied-line-space gratings and can reach some precision. Finally, the method is suggested into fabrication of holographic varied-line-space gratings.

In order to derive the effect of an arbitrary bending curve in tangential orientation on a grating,a general expression about the transform of groove density was represented in theory,and simulated by Finite Element Method(FEM) using ABAQUS/Standard.The results show that the groove density was severely determined by the attribute of diffractive grating and bending curve.Sequentially,the imaging properties of grating monochromator due to bending were numerically pointed out with a simple example.As...

In order to derive the effect of an arbitrary bending curve in tangential orientation on a grating,a general expression about the transform of groove density was represented in theory,and simulated by Finite Element Method(FEM) using ABAQUS/Standard.The results show that the groove density was severely determined by the attribute of diffractive grating and bending curve.Sequentially,the imaging properties of grating monochromator due to bending were numerically pointed out with a simple example.As a result of shape change and groove density variation,it not only improves the focusing condition,but also affectes higher order aberrations such as coma aberration of the imaging system.