Abstract:
A novel means of provided velocity control of an interferometer wherein one of the moving components includes the beamsplitter element is introduced herein. Using a moving beamsplitter and coupled flexure mounting allows improved velocity control because the low mass of the beamsplitter enables the systems disclosed herein to respond faster than conventional mirror velocity controlled interferometer instruments with a resultant lower velocity error so as to provide a more stable and lower noise spectra from the analytical instrument. The control of the velocity of the beamsplitter and if desired, one or both of the configured mirrors, reduces the time wasted changing velocity at the ends of each scan. The result is an increase in data collection available in any given experiment time frame. Such desirable arrangements of the present invention thus allow scans to be collected at higher rates, which beneficially increase the ability to monitor rapidly changing systems.
Abstract:
L'invention concerne un procédé de métrologie d'un interféromètre (1) statique comprenant une lame (3) séparatrice apte à séparer un faisceau incident (2) vers un premier (M1) et un deuxième miroirs (M2), le premier miroir (M1) présentant N surfaces (S 1 , S 2 , S 3 ... ,S N ) réfléchissantes sensiblement planes et parallèles entre elles, lesdites surfaces étant décalées entre elles et réalisant N premières hauteurs de marche (h M1 (x)), le deuxième miroir (M2) présentant M surfaces (S' 1 , S' 2 , S' 3 ... ,S' M ) réfléchissantes sensiblement planes et parallèles entre elles, lesdites surfaces étant décalées entre elles et réalisant M deuxièmes hauteurs de marche (h M2 (y)), les hauteurs de marche (h M1 (x),h M2 (y)) correspondant à la distance entre chaque surface (S 1 , S 2 , S 3 ... ,S N , S' 1 , S' 2 , S' 3 ... ,S' M ) et la lame (3), de sorte que les deux miroirs (M1,M2) fournissent une pluralité de faisceaux réfléchis présentant entre eux des différences de chemin optique (δ(x,y)) égales aux N*M sommes croisées des premières hauteurs de marche (h M1 (x)) et des deuxièmes hauteurs de marche (h M2 (y)), ledit procédé étant caractérisé en ce qu'il comprend au moins les étapes consistant à : - acquérir un interférogramme d'intensité (I(x,y)) à partir d'un faisceau (2) incident monochromatique, - estimer (22) lesdites N+M premières et deuxièmes hauteurs de marche (h M1 (x);h M2 (y)) par résolution d'un système d'équations liant l'intensité I(x,y) mesurée aux N+M premières et deuxièmes hauteurs de marche, ledit système exploitant les corrélations et dépendances géométriques des miroirs, - déduire (23) les N*M différences de chemin optique (δ(x,y)) à partir des N+M premières et deuxièmes hauteurs de marche.
Abstract:
In accordance with the invention, an improved optical assembly (200) having a monolithic structure is provided. The monolithic optical assembly (200) is useful in interferometers to achieve a fringe effect in a Fourier transform spectrometer, and comprises top (260) and bottom members (270) which are joined into a monolithic structure by first (210) and second support members (220) and a beamsplitter (130). The assembly also comprising a first reflecting assembly (140) in reflecting relation with the beamsplitter (130). An alternate embodiment of the invention has an added reflecting assembly (150) in reflecting relation with the first reflecting assembly (140) and the beamsplitter assembly (130), which allows for the use of multiple wavelength light sources to achieve a fringe effect in a Fourier transform spectrometer.
Abstract:
La présente invention concerne un système optique pour spectromètre à transformée de Fourier destiné à des missions de sondage atmosphérique et comprenant un interféromètre. Le système optique selon l'invention comprend un dispositif optique apte à rapprocher les projections des points de sondage (P0, P1' à P8') du centre du champ de l'interféromètre. Ce système présente notamment l'avantage de permettre augmentation de la capacité d'étendue des interféromètres tout en conservant l'étendue géométrique de chaque point de sondage.
Abstract:
An apparatus and method are provided. In particular, at least one first electro-magnetic radiation may be provided to a sample and at least one second electro-magnetic radiation can be provided to a non-reflective reference. A frequency of the first and/or second radiations varies over time. An interference is detected between at least one third radiation associated with the first radiation and at least one fourth radiation associated with the second radiation. Alternatively, the first electro-magnetic radiation and/or second electro-magnetic radiation have a spectrum which changes over time. The spectrum may contain multiple frequencies at a particular time. In addition, it is possible to detect the interference signal between the third radiation and the fourth radiation in a first polarization state. Further, it may be preferable to detect a further interference signal between the third and fourth radiations in a second polarization state which is different from the first polarization state. The first and/or second electro-magnetic radiations may have a spectrum whose mean frequency changes substantially continuously over time at a tuning speed that is greater than 100 Tera Hertz per millisecond.
Abstract:
An apparatus and method are provided. In particular, at least one first electro-magnetic radiation may be provided to a sample and at least one second electro-magnetic radiation can be provided to a non-reflective reference. A frequency of the first and/or second radiations varies over time. An interference is detected between at least one third radiation associated with the first radiation and at least one fourth radiation associated with the second radiation. Alternatively, the first electro-magnetic radiation and/or second electro-magnetic radiation have a spectrum which changes over time. The spectrum may contain multiple frequencies at a particular time. In addition, it is possible to detect the interference signal between the third radiation and the fourth radiation in a first polarization state. Further, it may be preferable to detect a further interference signal between the third and fourth radiations in a second polarization state which is different from the first polarization state. The first and/or second electro-magnetic radiations may have a spectrum whose mean frequency changes substantially continuously over time at a tuning speed that is greater than 100 Tera Hertz per millisecond.