Optoelectronic element with a non-protruding lens

• US 7,067,893 B2
• Filed: 01/03/2003
• Issued: 06/27/2006
• Est. Priority Date: 03/10/1998
• Status: Expired due to Term

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Coffin, James P. IV, Mills, Michael A.
• Primary Examiner(s): Cao, Phat X.
• Assistant Examiner(s): Doan, Theresa T.
• Application Number:
  US10/337,058
• Publication Number:
  US 20030132495A1
• Time in Patent Office: 1,271 Days
• Field of Search: 257/433, 257/432, 257 79- 84, 257 99-100, 257428-436, 257/787
• US Class Current: 257/433
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: B29C 45/14655 connected to or mounted on a carrier, e.g. lead frame
• CPC Class Codes: B29C 45/401 Ejector pin constructions or mountings
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01077 Iridium [Ir]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2924/12043 Photo diode
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/1815 Shape
• CPC Class Codes: H01L 31/0203 Containers; Encapsulations , e.g. encapsulation of photodiodesfor photovoltaic devices H01L31/048; for organic photosensitive devices H10K30/80
• CPC Class Codes: H01L 31/02327 the optical elements being integrated or being directly associated to the device, e.g. back reflectors optical coatings H01L31/0216
• CPC Class Codes: H01L 33/54 : having a particular shape
• CPC Class Codes: Y10S 425/808 : Lens mold

Abstract

An optoelectronic component has a lens that is formed in the surface of an encapsulant surrounding a semiconductor diode element. With respect to emitters, the lens reduces internal reflection and reduces dispersion to increase overall efficiency. With respect to detectors, the lens focuses photons on the active area of the detector, increasing detector sensitivity, which allows a detector having a reduced size and reduced cost for a given application. The lens portion of the encapsulant is generally nonprotruding from the surrounding portions of the encapsulant reducing contact surface pressure caused by the optoelectronic component. This non-protruding lens is particularly useful in pulse oximetry sensor applications. The lens is advantageously formed with a contoured-tip ejector pin incorporated into the encapsulant transfer mold, and the lens shape facilitates mold release.

Claims

1. A non-reflectance pulse oximetry sensor capable of being positioned in proximity to a person'"'"'s skin, the pulse oximetry sensor comprising:

an encapsulant having a surface positionable in proximity to the skin;

a lens comprising a curved lens portion of the surface of the encapsulant;

a generally smooth portion of the surface of the encapsulant, wherein the lens does not protrude substantially beyond the generally smooth portion, thereby avoiding forming a pressure necrosis at the skin;

a trough between the curved lens portion and the generally smooth portion of the surface of the encapsulant, the trough having a sidewall spaced from the lens; and

an optoelectronic element embedded in the encapsulant, the optoelectronic element emitting light through at least a portion of the lens to the skin.

2. The non-reflectance pulse oximetry sensor of claim 1, wherein the non-reflectance pulse oximetry sensor is a transmission pulse oximetry sensor.

3. The non-reflectance pulse oximetry sensor of claim 1, wherein the optoelectronic element comprises a first light emitting diode operable to transmit light through at least a portion of the lens.

4. The non-reflectance pulse oximetry sensor of claim 3, further comprising a second light emitting diode embedded in the encapsulant and operable to transmit light through at least a portion of the lens.

5. The non-reflectance pulse oximetry sensor of claim 4, wherein the first light emitting diode transmits wavelengths in the red portion of the electromagnetic spectrum and the second light emitting diode transmits wavelengths in the infrared portion of the electromagnetic spectrum.

6. The non-reflectance pulse oximetry sensor of claim 1, wherein the lens further comprises a flat lens portion which lies substantially parallel to the generally smooth portion of the surface of the encapsulant.

7. The non-reflectance pulse oximetry sensor of claim 1, wherein the lens has a generally circular cross-section in at least one plane.

8. The non-reflectance pulse oximetry sensor of claim 1, wherein the lens has a generally parabolic cross-section in at least one plane.

9. The non-reflectance pulse oximetry sensor of claim 1, wherein the curved lens portion is spherically-curved.

10. The non-reflectance pulse oximetry sensor of claim 1, wherein the curved lens portion is parabolically-curved.