Abstract:
A flexible sensor with strain relief on electrical contacts. Wires are attached to the electrical contacts, then a bulge of material is deposited over them, such as an adhesive. The wires are then bent back over the top of the bulge and secured. This prevents any tugging on the cable from pulling directly on the attachment of the wires to the contacts.
Abstract:
A headband having a low stretch segment sized to fit around a wearer's head, and an elastic segment being smaller than the low stretch segment, and having a free end and an attached end, where the elastic segment is attached at its attached end with the low stretch segment. The headband also includes a tab portion having a first end and a second end, the first end of the tab portion being connected with the free end of the elastic portion, the second end of the tab portion configured to form a closed loop with the low stretch segment, around the wearer's head. The headband also includes visual indicator configured for monitoring the extended position of elastic segment and optionally a stop portion that is configured to engage against the elastic segment to limit its stretch. When having a stop portion, the tab portion also includes an indicator portion between its first end and the stop portion such that the indicator portion when visible indicates that the headband needs re-tightening; and when the indicator portion is not visible it indicates an adequate level of tension corresponding with delivering a pressure in the range higher than the venous pressure and lower than the capillary pressure to the forehead of the wearer.
Abstract:
The present invention relates to a method and apparatus for improving the durability of a sensor, specifically one attached by an adhesive material to a subject. Specifically, the present invention discloses a method and apparatus for laminating a sensor and inserting the sensor into a protective shield for use. The shield includes some adhesive material to affix the sensor to the subject. A dirty, damaged, or worn out shield may be discarded and the sensor inserted into a new shield for continued use of the sensor.
Abstract:
A pulse oximeter sensor having an emitter(s) and a detector, with a layer having a first portion of the emitter and a second portion of layer over the detector is provided. A barrier is included between the first and second portions of the overlying layer to substantially block radiation of the wavelengths emitted by the emitter(s). Preferably, the barrier reduces the radiation shunted to less than 10% of the radiation detected, and more preferably to less than 1% of the radiation detected.
Abstract:
A sensor has codes useful for a monitor which can be authenticated as accurate. The sensor produces a signal corresponding to a measured physiological characteristic and provides codes which can be assured of being accurate and authentic when used by a monitor. A memory associated with the sensor stores both data relating to the sensor and a digital signature. The digital signature authenticates the quality of the code by ensuring it was generated by an entity having predetermined quality controls, and ensures the code is accurate.
Abstract:
A non-invasive optical sensor which uses the motion signal to calculate the physiological characteristic being measured. For pulse oximetry, a least squares or a ratio-of-ratios technique can be applied to the motion signal itself. This is made possible by selecting a site on the patient where variations in motion produce signals of two wavelengths which are sufficiently correlated. In particular, it has been determined that a sensor placed on a nail, in particular a thumbnail, exhibits the characteristics of having the and infrared signals correlated when used for pulse oximetry, and the resulting signals correlate to arterial oxygen saturation.
Abstract:
A method for estimating the concentration of a particular gas in a gas mixture having a fluctuating pressure is provided. A sensor output signal indicating the concentration of a particular gas in the gas mixture is received from a gas sensor. The received sensor output signal may vary over time due to the fluctuating pressure of the gas mixture. The received sensor output signal may be processed to determine an estimate of the concentration of the particular gas in the gas mixture. The processing includes performing an autocorrelation of the signal. In some embodiments, the particular gas is oxygen and the method is used to estimate the concentration of oxygen in a gas mixture having a fluctuating pressure.
Abstract:
A sensor may be adapted to provide output to indicate when the sensor experiences abnormal forces or pressure. The forces may be outside forces, or the forces may be generated by patient motion. A sensor system as provided may also be adapted to correct for such forces when calculating measurements related to a physiological characteristic.
Abstract:
A noise-suppressing gas exhaust system for a gas delivery mask is provided. The system may include a face mask, an arm assembly, and a gas exhaust member. The face mask may be configured to interface with a subject's face. The arm. assembly may be configured to support the face mask. The gas exhaust member may be coupled to the arm assembly and may include a single gas passageway extending therethrough. The gas passageway may extend from a first opening formed in a first side of the gas exhaust member to a second opening formed in a second side of the gas exhaust member. The first opening may have a cross-sectional area of about 0.01 square inches to about 0.03 square inches, and the second opening may have a substantially larger cross-sectional area than the cross-sectional area of the first opening.
Abstract:
A method for preparing an aromatic chloroformate comprising, introducing a mixture of at least one aromatic hydroxy 1 compound, phosgene, at least one solvent, and at least one organic base into a flow reactor to obtain a unidirectionally flowing reaction mixture. The unidirectionally flowing reaction mixture is maintained at a temperature between about 00C and about 6O0C to produce a single product stream comprising an aromatic chlorof ormate . In another aspect a method for preparing a copolycarbonate . The method comprises reacting a dihydroxy aromatic compound under interfacial conditions with phosgene and the aromatic chlorof ormate .