High-resolution defocus compensating spectrograph
The present application discloses various embodiments of a high-resolution spectrograph. In one embodiment, the high-resolution spectrograph includes a light source, a housing, at least one adjustment device secured to the housing, and an optical detector secured to the adjustment device. At least one dispersive optical element is positioned in optical communication with the light source and the optical detector, wherein the dispersive optical element is configured to diffract at least a portion of an incident optical signal from the light source as a diffracted optical signal propagating toward the optical detector, wherein the optical detector is configured to measure at least one property at least one wavelength component of the diffracted optical signal. The adjustment device is configured to change the position of the optical detector relative to the dispersive optical element to optimize the image width of the wavelength component of the diffracted optical signal.
1 . A method of analyzing an incident optical signal, comprising:
providing at least one dispersive optical element operative to reflect the incident optical signal as a diffracted optical signal;
providing at least one detector configured to measure one or more properties of the diffracted optical signal;
providing at least one adjustment device operative to change a position of the at least one detector relative to the at least one dispersive optical element;
providing at least one controller configured to receive measurement data representative of the one or more properties of the diffracted optical signal from the at least one detector, and to command the at least one adjustment device to position the at least one detector relative to the at least one dispersive optical element;
measuring, with the at least one detector, at least one of the one or more properties of the diffracted optical signal;
adjusting the position of the detector relative to the at least one dispersive optical element with the at least one adjustment device until an optimum value of the at least one of the one or more properties of the diffracted optical signal is reached.
2 . The method of claim 1 , wherein one of the one or more properties of the diffracted optical signal is an optical power of at least one first wavelength component (λ 1 ).
3 . The method of claim 1 , wherein one of the one or more properties of the diffracted optical signal is an optical power of at least one second wavelength component (λ 2 ).
4 . The method of claim 1 , wherein one of the one or more properties of the diffracted optical signal is an optical power of at least one third wavelength component (λ 3 ).
5 . The method of claim 1 , wherein one of the one or more properties of the diffracted optical signal is an optical power of at least one fourth wavelength component (λ 4 ).
6 . The method of claim 1 , wherein one of the one or more properties of the diffracted optical signal is an optical power of at least one fifth wavelength component (λ 5 ).
7 . A method of analyzing an incident optical signal, comprising:
providing at least one dispersive optical element operative to reflect the incident optical signal as a diffracted optical signal;
providing at least one detector configured to measure one or more properties of the diffracted optical signal, wherein one of the one or more properties of the diffracted optical signal is an image width (W n ) of one or more wavelength components (λ n );
providing at least one adjustment device operative to change a position of the at least one detector relative to the at least one dispersive optical element;
providing at least one controller configured to receive measurement data representative of the image width (W n ) of a first wavelength component (λ1) from the at least one detector, and to command the at least one adjustment device to adjust the position of the at least one detector relative to the at least one dispersive optical element;
executing a control sequence, comprising:
in a first measurement step, measuring a first image width (W 1 ) of the first wavelength component (λ 1 ), with the at least one detector positioned at a first position (P 1 ) relative to the at least one dispersive optical element;
in a first motion step, positioning, with the at least one adjustment device, the at least one detector at a second position (P 0 ) relative to the at least one dispersive optical element;
in a second measurement step, measuring a second image width (W 2 ) of the first wavelength component (λ 1 ) with the at least one detector positioned at the second position (P 0 ) relative to at least one dispersive optical element;
in a comparison step comparing, in the at least one controller, the first image width (W 1 ) to the second image width (W 2 ) to determine a first change in image width (ΔW 1 );
if the first change in image width (ΔW 1 ) is positive, in a third motion step, positioning, with the at least one adjustment device, the at least one detector an incremental step (−ΔP 1 ) closer to the at least one dispersive optical element;
if the first change in image width (ΔW 1 ) is negative, in a second motion step, positioning, with the at least one adjustment device, the at least one detector the same incremental step (−ΔP 1 ) closer to the at least one dispersive optical element;
iterating the control sequence until a minimum image width (W min ) is reached; and
outputting data representative of the minimum image width (W min ) to at least one display.
8 . The method of claim 7 , further comprising repeating the control sequence for a second wavelength component (λ 2 ) of the diffracted optical signal.
9 . The method of claim 7 , further comprising repeating the control sequence for a third wavelength component (λ 3 ) of the diffracted optical signal.
10 . The method of claim 7 , further comprising repeating the control sequence for a fourth wavelength component (λ 4 ) of the diffracted optical signal.
11 . The method of claim 7 , further comprising repeating the control sequence for a fifth wavelength component (λ 5 ) of the diffracted optical signal.
12 . The method of claim 7 , further comprising repeating the control sequence for a sixth wavelength component (λ 6 ) of the diffracted optical signal.
13 . A method of analyzing an incident optical signal, comprising:
providing at least one dispersive optical element operative to diffract the incident optical signal as a diffracted optical signal;
providing at least one detector configured to measure one or more properties of the diffracted optical signal wherein one of the one or more properties of the diffracted optical signal is an image width (W n ) of one or more wavelength components (λ n );
providing an adjustment device operative to change a position of the at least one detector relative to the at least one dispersive optical element;
providing at least one detector controller configured to receive measurement data representative of at least one property of the diffracted optical signal from the at least one detector;
providing at least one motion controller configured to command the at least one adjustment device to adjust the position of the at least one detector relative to the at least one dispersive optical element;
executing a control sequence, comprising:
in a first measurement step, measuring, with the at least one detector positioned at a first position (P n ) relative to at least one dispersive optical element, a first image width (W n ) of a first wavelength component (λ1);
in a first data acquisition step, transmitting measurement data representative of the second image width (W n ) from the at least one detector to the at least one detector controller and transmitting detector data representative of the first position (P n ) relative to at least one adjustment device to the at least one motion controller;
in a first motion step, positioning, with the adjustment device, the detector a first incremental step (−ΔP n ) to a second position (P n−1 ) relative to the at least one dispersive optical element;
in a second measurement step, measuring, with the at least one detector positioned at the second position (P n−1 ) relative to at least one dispersive optical element, a second image width (W n+1 ) of the first wavelength component (λ 1 );
in a second data acquisition step, transmitting measurement data representative of the second image width (W n+1 ) from the at least one detector to the at least one detector controller and transmitting detector position data representative of the second position (P n−1 ) relative to the at least one adjustment device to the at least one motion controller;
in a second motion step, positioning, with the at least one adjustment device, the at least one detector a second incremental step (−ΔP n ) to a third position (P n−2 ) relative to the at least one dispersive optical element;
in a third measurement step, measuring, with the at least one detector positioned at the third position (P n−2 ) relative to the at least one dispersive optical element, a second image width (W n+2 ) of the first wavelength component (λ 1 );
in a third data acquisition step, transmitting measurement data representative of the third image width (W n+2 ) from the at least one detector to the at least one detector controller and transmitting detector position data representative of the third position (P n−2 ) of the at least one detector relative to the at least one adjustment device to the at least one motion controller;
in a compilation step, compiling in at least one controller the image width data and the detector position data from sequential data acquisition steps, and selecting a smallest image width (W min ) of the compiled image width data;
positioning the at least one detector at a distance (R min ) associated with the smallest image width (W min ).
14 . The method of claim 13 , further comprising repeating the control sequence for a second wavelength component (λ 2 ) of the diffracted optical signal.
15 . The method of claim 13 , further comprising repeating the control sequence for a third wavelength component (λ 3 ) of the diffracted optical signal.
16 . The method of claim 13 , further comprising repeating the control sequence for a fourth wavelength component (λ 4 ) of the diffracted optical signal.
17 . The method of claim 13 , further comprising repeating the control sequence for a fifth wavelength component (λ 5 ) of the diffracted optical signal.