Photographic lens, camera body, and camera system

• US 5,727,241 A
• Filed: 01/15/1997
• Issued: 03/10/1998
• Est. Priority Date: 01/24/1996
• Status: Expired due to Term

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Higaki, Riichi, Yamano, Shozo
• Primary Examiner(s): Perkey, W. B.
• Application Number:
  US08/782,320
• Time in Patent Office: 419 Days
• Field of Search: 396/279, 396/277, 396/303, 396/301, 396/302
• US Class Current: 396/279
• CPC Class Codes: G03B 17/14 interchangeably
• CPC Class Codes: G03B 7/26 Power supplies; Circuitry or arrangement to switch on the power source; Circuitry to check the power source voltage

Abstract

A camera system regulates electric power from a power supply within a camera body to a plurality of built-in actuators within a removable photographic lens. The actuators may include motors, solenoids, and the like which operate functions such as autofocus and image blur suppression. The photographic lens is equipped with a memory which stores data relating to the power supply characteristics of the built-in actuators. A transmission unit within the photographic lens transmits the stored data to a receiving unit within the camera body. A power supply characteristics measurement unit within the camera body measures data relating to power supply characteristics of the electric power supply while a determination unit determines whether to supply electric power from the electric power supply to the actuators in response to all of the data. A display unit on the camera body displays a warning when no electric power is supplied to the actuator.

Claims

1. A camera system including a photographic lens mounted on a camera body having an electric power supply, comprising:

a first actuator disposed within the photographic lens which selectively receives electric power from the camera body;

a memory disposed within the photographic lens which stores first data relating to power supply characteristics for driving said first actuator;

a power supply measurement unit disposed within the camera body to calculate an equivalent output load resistance of the electric power supply by comparing non-load power supply voltage to load power supply voltage; and

a transmission unit disposed within the photographic lens which transmits the first data from said memory to the camera body,

wherein electric power is transmitted from the camera body to said first actuator based upon a comparison of the equivalent output load resistance and the first data.

2. The camera system according to claim 1, further comprising:

a power supply characteristics measurement unit disposed within the camera body which measures and acquires second data relating to power supply characteristics of the electric power supply; and

a determination unit disposed within the camera body which determines whether to supply electric power from the electric power supply to said first actuator in response to the first and second data.

3. The camera system according to claim 2, further comprising:

a first display unit disposed on the camera body which displays a warning when said determination unit determines not to supply electric power to said first actuator.

4. The camera system according to claim 2, further comprising:

a second actuator disposed within the photographic lens which receives electric power from the camera body;

wherein the first data stored in said memory relates to power supply characteristics for driving said first and second actuators, and said determination unit determines whether to supply electric power from the electric power supply to said first and second actuators in response to the first and second data.

5. The camera system according to claim 2, further comprising:

a second actuator disposed within the photographic lens which receives electric power from the camera body and which selectively operates simultaneously or sequentially with respect to said first actuator;

wherein the first data stored in said memory relates to power supply characteristics for driving said first and second actuators, and said determination unit determines whether to supply electric power from the electric power supply to said first and second actuators simultaneously or sequentially.

6. The camera system according to claim 1, further comprising:

a power supply data accumulation unit disposed within the camera body which accumulates the first data from said transmission unit;

a power supply characteristics measurement unit disposed within the camera body which measures and acquires second data relating to power supply characteristics of the electric power supply; and

a determination unit disposed within the camera body which determines whether to supply electric power from the electric power supply to said first actuator in response to the first data from said power supply data accumulation unit and the second data from said power supply characteristics measurement unit.

7. The camera system according to claim 1, further comprising:

a first receiving unit disposed within the photographic lens which receives second data relating to power supply characteristics of the electric power supply from the camera body; and

a determination unit disposed within the photographic lens which requests electric power to be supplied from the electric power supply to said first actuator in response to the first and second data.

8. The camera system according to claim 1, further comprising:

a determination unit disposed within the camera body which determines whether to supply electric power from the electric power supply to said first actuator in response to the first data; and

a first display unit disposed on the camera body which displays a warning when said determination unit determines not to supply electric power from the electric power supply to said first actuator.

9. A photographic lens which is mountable on a camera body having an electric power supply, comprising:

a first actuator which selectively receives electric power from the electric power supply;

a memory which stores first data relating to power supply characteristics for driving said first actuator; and

a receiving unit which receives second data relating to power supply characteristics of the electric power supply,

wherein the second data is a calculated equivalent output load resistance of the electric power supply through comparison of non-load power supply voltage to load power supply voltage, and electric power is transmitted from the camera body to said first actuator based upon a comparison of the first and second data.

10. The photographic lens according to claim 9, further comprising:

a determination unit which determines whether the electric power supply can supply electric power for driving said first actuator from the first and second data.

11. The photographic lens according to claim 10, further comprising:

a second actuator disposed within the photographic lens which receives electric power from the camera body;

wherein the first data stored in said memory relates to power supply characteristics for driving said first and second actuators, and said determination unit determines whether to supply electric power from the electric power supply to said first and second actuators in response to the first and second data.

12. The photographic lens according to claim 10, further comprising:

a second actuator disposed within the photographic lens which receives electric power from the camera body and which selectively operates simultaneously or sequentially with respect to said first actuator;

wherein the first data stored in said memory relates to power supply characteristics for driving said first and second actuators, and said determination unit determines whether to supply electric power from the electric power supply to said first and second actuators simultaneously or sequentially.

13. The photographic lens according to claim 10, further comprising:

a transmission unit which transmits a decision result from said determination unit to the camera body.

14. A camera body having an internal electric power supply and mounted to a photographic lens, comprising:

a power supply characteristics measurement unit which measures and acquires first data relating to power supply characteristics of the electric power supply by comparing non-load power supply voltage to load power supply voltage;

a transmission unit which selectively transmits the first data from the power supply characteristics measurement unit to the mounted photographic lens; and

a receiving unit which receives decision results indicating actuator power requirements from the mounted photographic lens,

wherein electric power is transmitted from the camera body to the mounted photographic lens based upon a comparison of the first data and the decision results.

15. The camera body according to claim 14, further comprising:

a first display unit which displays a warning when the decision results received by said receiving unit indicate insufficient power to operate a lens actuator in the photographic lens.

16. The camera body according to claim 14, further comprising:

a second display unit which performs an inhibition display when the decision results indicate that the lens actuator does not require power.

17. The camera body according to claim 16, further comprising:

plural actuators including said lens actuator;

a timing adjustment unit which inhibits said plural actuators from being driven simultaneously.

18. A camera body according to claim 14, further comprising:

a timing adjustment unit which inhibits plural actuators from being driven simultaneously according to the decision results of said determination unit when a power requirement of said actuator competes with the requirements of the photographic lens and the camera body.

19. A camera system including a photographic lens mounted on a camera body, comprising:

an electric power supply disposed within the camera body;

an actuator disposed within the photographic lens which receives electric power from the electric power supply;

a memory disposed within the photographic lens which stores first data relating to power supply characteristics for driving said actuator;

a transmission unit disposed within the photographic lens which transmits the first data from said memory to the camera body;

a power supply data accumulation unit disposed within the camera body which receives the first data from the transmission unit;

a power supply characteristics measurement unit disposed within the camera body which measures and acquires second data relating to power supply characteristics of the electric power supply by comparing non-load power supply voltage to load power supply voltage; and

a determination unit disposed within the camera body which determines whether to supply electric power from the electric power supply to said actuator in response to a received actuator drive demand, the first data and the second data.

20. The camera system according to claim 19, further comprising:

a second actuator disposed within the photographic lens which receives electric power from the camera body;

wherein the first data stored in said memory relates to power supply characteristics for driving said first and second actuators, and said determination unit determines whether to supply electric power from the electric power supply to said first and second actuator in response to the first and second data.