Abstract: A method of controlling a tuneable laser that has been characterized with respect to one or more suitable laser operation points. Each operation point is determined by the manner in which the different laser sections are controlled, in order to operate the laser at a predetermined operation point. The voltage across the different laser section is determined for different operation points when controlling the laser, and the voltages across the different laser sections are held constant when the laser is in operation to maintain a predetermined operation point.

Abstract: A method of optimizing the operation point of a laser, including characterizing the laser and controlling the different laser sections by varying the currents injected into the respective laser sections. The method includes sensing discontinuities that occur at mode jumps in a signal by utilizing a detection device that is firmly connected to the laser. Control of the different laser sections is effected by means of a control unit. Different control current combinations and the signal delivered by the detection device are provided to the control unit, which causes the control unit to detect the mode plane of the laser. At least a part of a mode plane, or several mode planes, are stored in a memory connected with the control unit, and the control unit controls the different laser sections so that the laser will operate at the desired operation point.

Abstract: The present invention relates to an approach to locking the output wavelength of a laser that uses an etalon having non-parallel surfaces. Under this approach, the non-parallel etalon is formed from a readily available, low cost optical component, and may include an etalon with a wedged shape or with at least one curved surface. This approach offers significant advantages over the use of a planar etalon. It provides two degrees of freedom in alignment of the device, and so both the absolute wavelength and the spacing between the interference fringes can be independently adjusted. It also reduces the cost and difficulty of assembly, since it utilizes standard optical parts with wide tolerances. The invention may be used within a standard laser package. The invention also permits the laser to be tuned to a precise operating wavelength by setting various tuning signals according to values stored in memory.

Abstract: The present invention relates to an approach to locking the output wavelength of a laser that uses an etalon having non-parallel surfaces. Under this approach, the non-parallel etalon is formed from a readily available, low cost optical component, and may include an etalon with a wedged shape or with at least one curved surface. This approach offers significant advantages over the use of a planar etalon. It provides two degrees of freedom in alignment of the device, and so both the absolute wavelength and the spacing between the interference fringes can be independently adjusted. It also reduces the cost and difficulty of assembly, since it utilizes standard optical parts with wide tolerances. The invention may be used within a standard laser package. The invention also permits the laser to be tuned to a precise operating wavelength by setting various tuning signals according to values stored in memory.

Abstract: A method for converting a representation of a ventilation duct system in a computer readable form from a first duct type to a second duct type, such as circular and rectangular ducts. The method identifies straight duct elements in the system, calculates an equivalent size of one or several duct elements of the second duct type to provide the same performance as the duct elements of the first duct type; and connects the duct element of the second duct type with connection duct elements in accordance with the connection of the corresponding elements in the original ventilation system, whereby a converted representation of the ventilation system is obtained.

Abstract: A method for automatically generating and connecting a text string to an installation element in a representation of an installation system in a computer readable form, such as a CAD-drawing. The text string indicates the properties of said element in said installation system. The method comprises the steps of identifying the type of said installation element; reading for each element, from a database, predetermined rules and a text pattern corresponding to the type of said element. Further, the method comprises the steps of combining, from said representation of an installation system, the properties of said element, such as dimensions, with said text pattern to produce a text string for said element; and connecting said text string with said element in said representation.